treturn of venti - plan9port - [fork] Plan 9 from user space
git clone git://src.adamsgaard.dk/plan9port
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---
commit a0d146edd7a7de6236a0d60baafeeb59f8452aae
parent 88bb285e3d87ec2508840af33f7e0af53ec3c13c
Author: rsc 
Date:   Tue, 12 Jul 2005 15:23:36 +0000

return of venti

Diffstat:
  A src/cmd/venti/copy.c                |     170 +++++++++++++++++++++++++++++++
  A src/cmd/venti/devnull.c             |      80 +++++++++++++++++++++++++++++++
  M src/cmd/venti/mkfile                |      14 ++++++++++++--
  A src/cmd/venti/mkroot.c              |      59 +++++++++++++++++++++++++++++++
  A src/cmd/venti/randtest.c            |     334 +++++++++++++++++++++++++++++++
  A src/cmd/venti/read.c                |      75 +++++++++++++++++++++++++++++++
  A src/cmd/venti/readlist.c            |     112 +++++++++++++++++++++++++++++++
  A src/cmd/venti/ro.c                  |     112 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/arena.c           |     737 ++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/arenas.c          |     414 ++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/bloom.c           |     210 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/buildbuck.c       |     132 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/buildindex.c      |     160 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/checkarenas.c     |     135 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/checkindex.c      |     293 ++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/clump.c           |     222 ++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/clumpstats.c      |     127 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/config.c          |     245 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/conv.c            |     632 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/dat.h             |     718 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/dcache.c          |     816 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/dump.c            |      47 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/findscore.c       |     121 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/fmtarenas.c       |     135 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/fmtbloom.c        |     115 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/fmtindex.c        |     120 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/fmtisect.c        |      83 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/fns.h             |     206 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/graph.c           |     202 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/httpd.c           |     988 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/icache.c          |     348 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/icachewrite.c     |     318 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/ifile.c           |      93 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/index.c           |     819 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/lump.c            |     249 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/lumpcache.c       |     417 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/lumpqueue.c       |     187 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/mkfile            |     146 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/part.c            |     383 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/png.c             |     241 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/printarena.c      |     130 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/printarenas.c     |     113 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/printindex.c      |      99 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/printmap.c        |      42 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/rdarena.c         |      91 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/round.c           |     102 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/score.c           |      43 ++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/sortientry.c      |     376 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/stats.c           |     212 ++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/stdinc.h          |       9 +++++++++
  A src/cmd/venti/srv/syncarena.c       |     174 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/syncindex.c       |      73 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/syncindex0.c      |     167 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/trace.c           |      38 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/unittoull.c       |      30 ++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/unwhack.c         |     179 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/utils.c           |     252 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/venti.c           |     266 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/verifyarena.c     |     127 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/whack.c           |     331 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/whack.h           |      40 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/wrarena.c         |     217 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/xml.c             |      68 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/xml.h             |      11 +++++++++++
  A src/cmd/venti/srv/zblock.c          |      93 +++++++++++++++++++++++++++++++
  A src/cmd/venti/srv/zeropart.c        |      31 +++++++++++++++++++++++++++++++
  A src/cmd/venti/sync.c                |      54 +++++++++++++++++++++++++++++++
  A src/cmd/venti/write.c               |      62 +++++++++++++++++++++++++++++++

68 files changed, 14443 insertions(+), 2 deletions(-)
---
diff --git a/src/cmd/venti/copy.c b/src/cmd/venti/copy.c
t@@ -0,0 +1,170 @@
+#include 
+#include 
+#include 
+#include 
+#include 
+
+int changes;
+int rewrite;
+int ignoreerrors;
+int fast;
+int verbose;
+VtConn *zsrc, *zdst;
+
+void
+usage(void)
+{
+        fprint(2, "usage: copy [-fir] [-t type] srchost dsthost score\n");
+        threadexitsall("usage");
+}
+
+void
+walk(uchar score[VtScoreSize], uint type, int base)
+{
+        int i, n;
+        uchar *buf;
+        VtEntry e;
+        VtRoot root;
+
+        if(memcmp(score, vtzeroscore, VtScoreSize) == 0)
+                return;
+
+        buf = vtmallocz(VtMaxLumpSize);
+        if(fast && vtread(zdst, score, type, buf, VtMaxLumpSize) >= 0){
+                if(verbose)
+                        fprint(2, "skip %V\n", score);
+                free(buf);
+                return;
+        }
+
+        n = vtread(zsrc, score, type, buf, VtMaxLumpSize);
+        if(n < 0){
+                if(rewrite){
+                        changes++;
+                        memmove(score, vtzeroscore, VtScoreSize);
+                }else if(!ignoreerrors)
+                        sysfatal("reading block %V (type %d): %r", type, score);
+                return;
+        }
+
+        switch(type){
+        case VtRootType:
+                if(vtrootunpack(&root, buf) < 0){
+                        fprint(2, "warning: could not unpack root in %V %d\n", score, type);
+                        break;
+                }
+                walk(root.score, VtDirType, 0);
+                walk(root.prev, VtRootType, 0);
+                vtrootpack(&root, buf);        /* walk might have changed score */
+                break;
+
+        case VtDirType:
+                for(i=0; i= 0)
+                                break;
+                }
+                if(type == VtMaxType)
+                        sysfatal("could not find block %V of any type", score);
+        }
+
+        walk(score, type, VtDirType);
+        if(changes)
+                print("%s:%V (%d pointers rewritten)\n", prefix, score, changes);
+
+        if(vtsync(zdst) < 0)
+                sysfatal("could not sync dst server: %r");
+
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/devnull.c b/src/cmd/venti/devnull.c
t@@ -0,0 +1,80 @@
+/* Copyright (c) 2004 Russ Cox */
+#include 
+#include 
+#include 
+#include 
+#include 
+
+#ifndef _UNISTD_H_
+#pragma varargck type "F" VtFcall*
+#pragma varargck type "T" void
+#endif
+
+int verbose;
+
+enum
+{
+        STACK = 8192,
+};
+
+void
+usage(void)
+{
+        fprint(2, "usage: venti/devnull [-v] [-a address]\n");
+        threadexitsall("usage");
+}
+
+void
+threadmain(int argc, char **argv)
+{
+        VtReq *r;
+        VtSrv *srv;
+        char *address;
+        Packet *p;
+
+        fmtinstall('V', vtscorefmt);
+        fmtinstall('F', vtfcallfmt);
+        
+        address = "tcp!*!venti";
+
+        ARGBEGIN{
+        case 'v':
+                verbose++;
+                break;
+        case 'a':
+                address = EARGF(usage());
+                break;
+        default:
+                usage();
+        }ARGEND
+
+        srv = vtlisten(address);
+        if(srv == nil)
+                sysfatal("vtlisten %s: %r", argv[1]);
+
+        while((r = vtgetreq(srv)) != nil){
+                r->rx.msgtype = r->tx.msgtype+1;
+                if(verbose)
+                        fprint(2, "<- %F\n", &r->tx);
+                switch(r->tx.msgtype){
+                case VtTping:
+                        break;
+                case VtTgoodbye:
+                        break;
+                case VtTread:
+                        r->rx.error = vtstrdup("no such block");
+                        r->rx.msgtype = VtRerror;
+                        break;
+                case VtTwrite:
+                        packetsha1(r->tx.data, r->rx.score);
+                        break;
+                case VtTsync:
+                        break;
+                }
+                if(verbose)
+                        fprint(2, "-> %F\n", &r->rx);
+                vtrespond(r);
+        }
+        threadexitsall(nil);
+}
+
diff --git a/src/cmd/venti/mkfile b/src/cmd/venti/mkfile
t@@ -1,3 +1,13 @@
-%:VQ:
-        echo venti will return once it is debugged.
+<$PLAN9/src/mkhdr
+
+DIRS=srv
+
+TARG=\
+        copy\
+        read\
+        sync\
+        write\
+
+<$PLAN9/src/mkmany
+<$PLAN9/src/mkdirs
 
diff --git a/src/cmd/venti/mkroot.c b/src/cmd/venti/mkroot.c
t@@ -0,0 +1,59 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+char *host;
+
+void
+usage(void)
+{
+        fprint(2, "usage: mkroot [-h host] name type score blocksize prev\n");
+        threadexitsall("usage");
+}
+
+void
+threadmain(int argc, char *argv[])
+{
+        uchar score[VtScoreSize];
+        uchar buf[VtRootSize];
+        VtConn *z;
+        VtRoot root;
+
+        ARGBEGIN{
+        case 'h':
+                host = EARGF(usage());
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        if(argc != 5)
+                usage();
+
+        ventifmtinstall();
+
+        strecpy(root.name, root.name+sizeof root.name, argv[0]);
+        strecpy(root.type, root.type+sizeof root.type, argv[1]);
+        if(vtparsescore(argv[2], strlen(argv[2]), nil, root.score) < 0)
+                sysfatal("bad score '%s'", argv[2]);
+        root.blocksize = atoi(argv[3]);
+        if(vtparsescore(argv[4], strlen(argv[4]), nil, root.prev) < 0)
+                sysfatal("bad score '%s'", argv[4]);
+        vtrootpack(&root, buf);
+
+        z = vtdial(host);
+        if(z == nil)
+                sysfatal("could not connect to server: %r");
+
+        if(vtconnect(z) < 0)
+                sysfatal("vtconnect: %r");
+
+        if(vtwrite(z, score, VtRootType, buf, VtRootSize) < 0)
+                sysfatal("vtwrite: %r");
+        if(vtsync(z) < 0)
+                sysfatal("vtsync: %r");
+        vthangup(z);
+        print("%V\n", score);
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/randtest.c b/src/cmd/venti/randtest.c
t@@ -0,0 +1,334 @@
+#include 
+#include 
+#include 
+#include 
+#include 
+
+
+enum { STACK = 32768 };
+void xxxsrand(long);
+long xxxlrand(void);
+
+Channel *cw;
+Channel *cr;
+char *host;
+int blocksize, seed, randpct;
+int doread, dowrite, packets, permute;
+vlong totalbytes, cur;
+VtConn *z;
+int multi;
+int maxpackets;
+int sequence;
+int doublecheck = 1;
+uint *order;
+
+void
+usage(void)
+{
+        fprint(2, "usage: randtest [-q] [-h host] [-s seed] [-b blocksize] [-p randpct] [-n totalbytes] [-M maxblocks] [-P] [-r] [-w]\n");
+        threadexitsall("usage");
+}
+
+void
+wr(char *buf, char *buf2)
+{
+        uchar score[VtScoreSize], score2[VtScoreSize];
+        DigestState ds;
+
+        memset(&ds, 0, sizeof ds);
+        if(doublecheck)
+                sha1((uchar*)buf, blocksize, score, &ds);
+        if(vtwrite(z, score2, VtDataType, (uchar*)buf, blocksize) < 0)
+                sysfatal("vtwrite %V at %,lld: %r", score, cur);
+        if(doublecheck && memcmp(score, score2, VtScoreSize) != 0)
+                sysfatal("score mismatch! %V %V", score, score2);
+}
+
+void
+wrthread(void *v)
+{
+        char *p;
+
+        USED(v);
+        while((p = recvp(cw)) != nil){
+                wr(p, nil);
+                free(p);
+        }
+}
+
+void
+rd(char *buf, char *buf2)
+{
+        uchar score[VtScoreSize];
+        DigestState ds;
+
+        memset(&ds, 0, sizeof ds);
+        sha1((uchar*)buf, blocksize, score, &ds);
+        if(vtread(z, score, VtDataType, (uchar*)buf2, blocksize) < 0)
+                sysfatal("vtread %V at %,lld: %r", score, cur);
+        if(memcmp(buf, buf2, blocksize) != 0)
+                sysfatal("bad data read! %V", score);
+}
+
+void
+rdthread(void *v)
+{
+        char *p, *buf2;
+
+        buf2 = vtmalloc(blocksize);
+        USED(v);
+        while((p = recvp(cr)) != nil){
+                rd(p, buf2);
+                free(p);
+        }
+}
+
+char *template;
+
+void
+run(void (*fn)(char*, char*), Channel *c)
+{
+        int i, t, j, packets;
+        char *buf2, *buf;
+
+        buf2 = vtmalloc(blocksize);
+        buf = vtmalloc(blocksize);
+        cur = 0;
+        packets = totalbytes/blocksize;
+        if(maxpackets == 0)
+                maxpackets = packets;
+        order = vtmalloc(packets*sizeof order[0]);
+        for(i=0; i= 0)
+                        rng_vec[i] = x;
+        }
+}
+
+void
+xxxsrand(long seed)
+{
+        isrand(seed);
+}
+
+long
+xxxlrand(void)
+{
+        ulong x;
+
+        rng_tap--;
+        if(rng_tap < rng_vec) {
+                if(rng_feed == 0) {
+                        isrand(1);
+                        rng_tap--;
+                }
+                rng_tap += LEN;
+        }
+        rng_feed--;
+        if(rng_feed < rng_vec)
+                rng_feed += LEN;
+        x = (*rng_feed + *rng_tap) & MASK;
+        *rng_feed = x;
+
+        return x;
+}
+
diff --git a/src/cmd/venti/read.c b/src/cmd/venti/read.c
t@@ -0,0 +1,75 @@
+#include 
+#include 
+#include 
+#include 
+#include 
+
+void
+usage(void)
+{
+        fprint(2, "usage: read [-h host] [-t type] score\n");
+        threadexitsall("usage");
+}
+
+void
+threadmain(int argc, char *argv[])
+{
+        int type, n;
+        uchar score[VtScoreSize];
+        uchar *buf;
+        VtConn *z;
+        char *host;
+
+        fmtinstall('F', vtfcallfmt);
+        fmtinstall('V', vtscorefmt);
+
+        host = nil;
+        type = -1;
+        ARGBEGIN{
+        case 'h':
+                host = EARGF(usage());
+                break;
+        case 't':
+                type = atoi(argv[1]);
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        if(argc != 1)
+                usage();
+
+        if(vtparsescore(argv[0], nil, score) < 0)
+                sysfatal("could not parse score '%s': %r", argv[0]);
+
+        buf = vtmallocz(VtMaxLumpSize);
+
+        z = vtdial(host);
+        if(z == nil)
+                sysfatal("could not connect to server: %r");
+
+        if(vtconnect(z) < 0)
+                sysfatal("vtconnect: %r");
+
+        if(type == -1){
+                n = -1;
+                for(type=0; type= 0){
+                                fprint(2, "venti/read%s%s %V %d\n", host ? " -h" : "", host ? host : "",
+                                        score, type);
+                                break;
+                        }
+                }
+        }else{
+                type = atoi(argv[1]);
+                n = vtread(z, score, type, buf, VtMaxLumpSize);
+        }
+        vthangup(z);
+        if(n < 0)
+                sysfatal("could not read block: %r");
+        if(write(1, buf, n) != n)
+                sysfatal("write: %r");
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/readlist.c b/src/cmd/venti/readlist.c
t@@ -0,0 +1,112 @@
+#include 
+#include 
+#include 
+#include 
+#include 
+
+char *host;
+Biobuf b;
+VtConn *z;
+uchar *buf;
+void run(Biobuf*);
+int nn;
+
+void
+usage(void)
+{
+        fprint(2, "usage: readlist [-h host] list\n");
+        threadexitsall("usage");
+}
+
+int
+parsescore(uchar *score, char *buf, int n)
+{
+        int i, c;
+
+        memset(score, 0, VtScoreSize);
+
+        if(n != VtScoreSize*2){
+                werrstr("score wrong length %d", n);
+                return -1;
+        }
+        for(i=0; i= '0' && buf[i] <= '9')
+                        c = buf[i] - '0';
+                else if(buf[i] >= 'a' && buf[i] <= 'f')
+                        c = buf[i] - 'a' + 10;
+                else if(buf[i] >= 'A' && buf[i] <= 'F')
+                        c = buf[i] - 'A' + 10;
+                else {
+                        c = buf[i];
+                        werrstr("bad score char %d '%c'", c, c);
+                        return -1;
+                }
+
+                if((i & 1) == 0)
+                        c <<= 4;
+        
+                score[i>>1] |= c;
+        }
+        return 0;
+}
+
+void
+threadmain(int argc, char *argv[])
+{
+        int fd, i;
+
+        ARGBEGIN{
+        case 'h':
+                host = EARGF(usage());
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        fmtinstall('V', vtscorefmt);
+        buf = vtmallocz(VtMaxLumpSize);
+        z = vtdial(host);
+        if(z == nil)
+                sysfatal("could not connect to server: %r");
+        if(vtconnect(z) < 0)
+                sysfatal("vtconnect: %r");
+
+        if(argc == 0){
+                Binit(&b, 0, OREAD);
+                run(&b);
+        }else{
+                for(i=0; i
diff --git a/src/cmd/venti/ro.c b/src/cmd/venti/ro.c
t@@ -0,0 +1,112 @@
+/* Copyright (c) 2004 Russ Cox */
+#include 
+#include 
+#include 
+#include 
+#include 
+
+#ifndef _UNISTD_H_
+#pragma varargck type "F" VtFcall*
+#pragma varargck type "T" void
+#endif
+
+VtConn *z;
+int verbose;
+
+enum
+{
+        STACK = 8192,
+};
+
+void
+usage(void)
+{
+        fprint(2, "usage: venti/ro [-v] [-a address] [-h address]\n");
+        threadexitsall("usage");
+}
+
+void
+readthread(void *v)
+{
+        char err[ERRMAX];
+        VtReq *r;
+        uchar *buf;
+        int n;
+        
+        r = v;
+        buf = vtmalloc(r->tx.count);
+        if((n=vtread(z, r->tx.score, r->tx.blocktype, buf, r->tx.count)) < 0){
+                r->rx.msgtype = VtRerror;
+                rerrstr(err, sizeof err);
+                r->rx.error = vtstrdup(err);
+                free(buf);
+        }else{
+                r->rx.data = packetforeign(buf, n, free, buf);
+        }
+        if(verbose)
+                fprint(2, "-> %F\n", &r->rx);
+        vtrespond(r);
+}
+
+void
+threadmain(int argc, char **argv)
+{
+        VtReq *r;
+        VtSrv *srv;
+        char *address, *ventiaddress;
+
+        fmtinstall('F', vtfcallfmt);
+        fmtinstall('V', vtscorefmt);
+        
+        address = "tcp!*!venti";
+        ventiaddress = nil;
+        
+        ARGBEGIN{
+        case 'v':
+                verbose++;
+                break;
+        case 'a':
+                address = EARGF(usage());
+                break;
+        case 'h':
+                ventiaddress = EARGF(usage());
+                break;
+        default:
+                usage();
+        }ARGEND
+
+        if((z = vtdial(ventiaddress)) == nil)
+                sysfatal("vtdial %s: %r", ventiaddress);
+        if(vtconnect(z) < 0)
+                sysfatal("vtconnect: %r");
+
+        srv = vtlisten(address);
+        if(srv == nil)
+                sysfatal("vtlisten %s: %r", address);
+
+        while((r = vtgetreq(srv)) != nil){
+                r->rx.msgtype = r->tx.msgtype+1;
+                if(verbose)
+                        fprint(2, "<- %F\n", &r->tx);
+                switch(r->tx.msgtype){
+                case VtTping:
+                        break;
+                case VtTgoodbye:
+                        break;
+                case VtTread:
+                        threadcreate(readthread, r, 16384);
+                        continue;
+                case VtTwrite:
+                        r->rx.error = vtstrdup("read-only server");
+                        r->rx.msgtype = VtRerror;
+                        break;
+                case VtTsync:
+                        break;
+                }
+                if(verbose)
+                        fprint(2, "-> %F\n", &r->rx);
+                vtrespond(r);
+        }
+        threadexitsall(nil);
+}
+
diff --git a/src/cmd/venti/srv/arena.c b/src/cmd/venti/srv/arena.c
t@@ -0,0 +1,737 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+typedef struct ASum ASum;
+
+struct ASum
+{
+        Arena        *arena;
+        ASum        *next;
+};
+
+static void        sealarena(Arena *arena);
+static int        okarena(Arena *arena);
+static int        loadarena(Arena *arena);
+static CIBlock        *getcib(Arena *arena, int clump, int writing, CIBlock *rock);
+static void        putcib(Arena *arena, CIBlock *cib);
+static void        sumproc(void *);
+
+static QLock        sumlock;
+static Rendez        sumwait;
+static ASum        *sumq;
+static uchar zero[8192];
+
+int        arenasumsleeptime;
+
+int
+initarenasum(void)
+{
+        sumwait.l = &sumlock;
+
+        if(vtproc(sumproc, nil) < 0){
+                seterr(EOk, "can't start arena checksum slave: %r");
+                return -1;
+        }
+        return 0;
+}
+
+/*
+ * make an Arena, and initialize it based upon the disk header and trailer.
+ */
+Arena*
+initarena(Part *part, u64int base, u64int size, u32int blocksize)
+{
+        Arena *arena;
+
+        arena = MKZ(Arena);
+        arena->part = part;
+        arena->blocksize = blocksize;
+        arena->clumpmax = arena->blocksize / ClumpInfoSize;
+        arena->base = base + blocksize;
+        arena->size = size - 2 * blocksize;
+
+        if(loadarena(arena) < 0){
+                seterr(ECorrupt, "arena header or trailer corrupted");
+                freearena(arena);
+                return nil;
+        }
+        if(okarena(arena) < 0){
+                freearena(arena);
+                return nil;
+        }
+
+        if(arena->diskstats.sealed && scorecmp(zeroscore, arena->score)==0)
+                backsumarena(arena);
+
+        return arena;
+}
+
+void
+freearena(Arena *arena)
+{
+        if(arena == nil)
+                return;
+        free(arena);
+}
+
+Arena*
+newarena(Part *part, u32int vers, char *name, u64int base, u64int size, u32int blocksize)
+{
+        int bsize;
+        Arena *arena;
+
+        if(nameok(name) < 0){
+                seterr(EOk, "illegal arena name", name);
+                return nil;
+        }
+        arena = MKZ(Arena);
+        arena->part = part;
+        arena->version = vers;
+        if(vers == ArenaVersion4)
+                arena->clumpmagic = _ClumpMagic;
+        else{
+                do
+                        arena->clumpmagic = fastrand();
+                while(arena->clumpmagic==_ClumpMagic || arena->clumpmagic==0);
+        }
+        arena->blocksize = blocksize;
+        arena->clumpmax = arena->blocksize / ClumpInfoSize;
+        arena->base = base + blocksize;
+        arena->size = size - 2 * blocksize;
+
+        namecp(arena->name, name);
+
+        bsize = sizeof zero;
+        if(bsize > arena->blocksize)
+                bsize = arena->blocksize;
+
+        if(wbarena(arena)<0 || wbarenahead(arena)<0
+        || writepart(arena->part, arena->base, zero, bsize)<0){
+                freearena(arena);
+                return nil;
+        }
+
+        return arena;
+}
+
+int
+readclumpinfo(Arena *arena, int clump, ClumpInfo *ci)
+{
+        CIBlock *cib, r;
+
+        cib = getcib(arena, clump, 0, &r);
+        if(cib == nil)
+                return -1;
+        unpackclumpinfo(ci, &cib->data->data[cib->offset]);
+        putcib(arena, cib);
+        return 0;
+}
+
+int
+readclumpinfos(Arena *arena, int clump, ClumpInfo *cis, int n)
+{
+        CIBlock *cib, r;
+        int i;
+
+        for(i = 0; i < n; i++){
+                cib = getcib(arena, clump + i, 0, &r);
+                if(cib == nil)
+                        break;
+                unpackclumpinfo(&cis[i], &cib->data->data[cib->offset]);
+                putcib(arena, cib);
+        }
+        return i;
+}
+
+/*
+ * write directory information for one clump
+ * must be called the arena locked
+ */
+int
+writeclumpinfo(Arena *arena, int clump, ClumpInfo *ci)
+{
+        CIBlock *cib, r;
+
+        cib = getcib(arena, clump, 1, &r);
+        if(cib == nil)
+                return -1;
+        dirtydblock(cib->data, DirtyArenaCib);
+        packclumpinfo(ci, &cib->data->data[cib->offset]);
+        putcib(arena, cib);
+        return 0;
+}
+
+u64int
+arenadirsize(Arena *arena, u32int clumps)
+{
+        return ((clumps / arena->clumpmax) + 1) * arena->blocksize;
+}
+
+/*
+ * read a clump of data
+ * n is a hint of the size of the data, not including the header
+ * make sure it won't run off the end, then return the number of bytes actually read
+ */
+u32int
+readarena(Arena *arena, u64int aa, u8int *buf, long n)
+{
+        DBlock *b;
+        u64int a;
+        u32int blocksize, off, m;
+        long nn;
+
+        if(n == 0)
+                return -1;
+
+        qlock(&arena->lock);
+        a = arena->size - arenadirsize(arena, arena->memstats.clumps);
+        qunlock(&arena->lock);
+        if(aa >= a){
+                seterr(EOk, "reading beyond arena clump storage: clumps=%d aa=%lld a=%lld -1 clumps=%lld\n", arena->memstats.clumps, aa, a, arena->size - arenadirsize(arena, arena->memstats.clumps - 1));
+                return -1;
+        }
+        if(aa + n > a)
+                n = a - aa;
+
+        blocksize = arena->blocksize;
+        a = arena->base + aa;
+        off = a & (blocksize - 1);
+        a -= off;
+        nn = 0;
+        for(;;){
+                b = getdblock(arena->part, a, OREAD);
+                if(b == nil)
+                        return -1;
+                m = blocksize - off;
+                if(m > n - nn)
+                        m = n - nn;
+                memmove(&buf[nn], &b->data[off], m);
+                putdblock(b);
+                nn += m;
+                if(nn == n)
+                        break;
+                off = 0;
+                a += blocksize;
+        }
+        return n;
+}
+
+/*
+ * write some data to the clump section at a given offset
+ * used to fix up corrupted arenas.
+ */
+u32int
+writearena(Arena *arena, u64int aa, u8int *clbuf, u32int n)
+{
+        DBlock *b;
+        u64int a;
+        u32int blocksize, off, m;
+        long nn;
+        int ok;
+
+        if(n == 0)
+                return -1;
+
+        qlock(&arena->lock);
+        a = arena->size - arenadirsize(arena, arena->memstats.clumps);
+        if(aa >= a || aa + n > a){
+                qunlock(&arena->lock);
+                seterr(EOk, "writing beyond arena clump storage");
+                return -1;
+        }
+
+        blocksize = arena->blocksize;
+        a = arena->base + aa;
+        off = a & (blocksize - 1);
+        a -= off;
+        nn = 0;
+        for(;;){
+                b = getdblock(arena->part, a, off != 0 || off + n < blocksize ? ORDWR : OWRITE);
+                if(b == nil){
+                        qunlock(&arena->lock);
+                        return -1;
+                }
+                dirtydblock(b, DirtyArena);
+                m = blocksize - off;
+                if(m > n - nn)
+                        m = n - nn;
+                memmove(&b->data[off], &clbuf[nn], m);
+                // ok = writepart(arena->part, a, b->data, blocksize);
+                ok = 0;
+                putdblock(b);
+                if(ok < 0){
+                        qunlock(&arena->lock);
+                        return -1;
+                }
+                nn += m;
+                if(nn == n)
+                        break;
+                off = 0;
+                a += blocksize;
+        }
+        qunlock(&arena->lock);
+        return n;
+}
+
+/*
+ * allocate space for the clump and write it,
+ * updating the arena directory
+ZZZ question: should this distinguish between an arena
+filling up and real errors writing the clump?
+ */
+u64int
+writeaclump(Arena *arena, Clump *c, u8int *clbuf, u64int start, u64int *pa)
+{
+        DBlock *b;
+        u64int a, aa;
+        u32int clump, n, nn, m, off, blocksize;
+        int ok;
+        AState as;
+
+        n = c->info.size + ClumpSize + U32Size;
+        qlock(&arena->lock);
+        aa = arena->memstats.used;
+        if(arena->memstats.sealed
+        || aa + n + U32Size + arenadirsize(arena, arena->memstats.clumps + 1) > arena->size){
+                if(!arena->memstats.sealed){
+                        trace(0, "seal memstats %s", arena->name);
+                        arena->memstats.sealed = 1;
+                        as.arena = arena;
+                        as.aa = start+aa;
+                        as.stats = arena->memstats;
+                        setdcachestate(&as);
+                }
+                qunlock(&arena->lock);
+                return TWID64;
+        }
+        if(packclump(c, &clbuf[0], arena->clumpmagic) < 0){
+                qunlock(&arena->lock);
+                return TWID64;
+        }
+
+        /*
+         * write the data out one block at a time
+         */
+        blocksize = arena->blocksize;
+        a = arena->base + aa;
+        off = a & (blocksize - 1);
+        a -= off;
+        nn = 0;
+        for(;;){
+                b = getdblock(arena->part, a, off != 0 ? ORDWR : OWRITE);
+                if(b == nil){
+                        qunlock(&arena->lock);
+                        return TWID64;
+                }
+                dirtydblock(b, DirtyArena);
+                m = blocksize - off;
+                if(m > n - nn)
+                        m = n - nn;
+                memmove(&b->data[off], &clbuf[nn], m);
+        //        ok = writepart(arena->part, a, b->data, blocksize);
+                ok = 0;
+                putdblock(b);
+                if(ok < 0){
+                        qunlock(&arena->lock);
+                        return TWID64;
+                }
+                nn += m;
+                if(nn == n)
+                        break;
+                off = 0;
+                a += blocksize;
+        }
+
+        arena->memstats.used += c->info.size + ClumpSize;
+        arena->memstats.uncsize += c->info.uncsize;
+        if(c->info.size < c->info.uncsize)
+                arena->memstats.cclumps++;
+
+        clump = arena->memstats.clumps++;
+        if(arena->memstats.clumps == 0)
+                sysfatal("clumps wrapped");
+        arena->wtime = now();
+        if(arena->ctime == 0)
+                arena->ctime = arena->wtime;
+
+        writeclumpinfo(arena, clump, &c->info);
+
+        /* set up for call to setdcachestate */
+        as.arena = arena;
+        as.aa = start+arena->memstats.used;
+        as.stats = arena->memstats;
+
+        /* update this before calling setdcachestate so it cannot be behind dcache.diskstate */
+        *pa = start+aa;
+        setdcachestate(&as);
+        qunlock(&arena->lock);
+
+        return aa;
+}
+
+int
+atailcmp(ATailStats *a, ATailStats *b)
+{
+        /* good test */
+        if(a->used < b->used)
+                return -1;
+        if(a->used > b->used)
+                return 1;
+                
+        /* suspect tests - why order this way? (no one cares) */
+        if(a->clumps < b->clumps)
+                return -1;
+        if(a->clumps > b->clumps)
+                return 1;
+        if(a->cclumps < b->cclumps)
+                return -1;
+        if(a->cclumps > b->cclumps)
+                return 1;
+        if(a->uncsize < b->uncsize)
+                return -1;
+        if(a->uncsize > b->uncsize)
+                return 1;
+        if(a->sealed < b->sealed)
+                return -1;
+        if(a->sealed > b->sealed)
+                return 1;
+                
+        /* everything matches */
+        return 0;
+}
+
+void
+setatailstate(AState *as)
+{
+        int i, j, osealed;
+        Arena *a;
+        Index *ix;
+
+        trace(0, "setatailstate %s 0x%llux clumps %d", as->arena->name, as->aa, as->stats.clumps);
+
+        ix = mainindex;
+        for(i=0; inarenas; i++)
+                if(ix->arenas[i] == as->arena)
+                        break;
+        if(i==ix->narenas || as->aa < ix->amap[i].start || as->aa >= ix->amap[i].stop || as->arena != ix->arenas[i]){
+                fprint(2, "funny settailstate 0x%llux\n", as->aa);
+                return;
+        }
+
+        for(j=i; --j>=0; ){
+                a = ix->arenas[j];
+                if(atailcmp(&a->diskstats, &a->memstats) == 0)
+                        break;
+        }
+        for(j++; j<=i; j++){
+                a = ix->arenas[j];
+                qlock(&a->lock);
+                osealed = a->diskstats.sealed;
+                if(j == i)
+                        a->diskstats = as->stats;
+                else
+                        a->diskstats = a->memstats;
+                wbarena(a);
+                if(a->diskstats.sealed != osealed && !a->inqueue)
+                        sealarena(a);
+                qunlock(&a->lock);
+        }
+}
+
+/*
+ * once sealed, an arena never has any data added to it.
+ * it should only be changed to fix errors.
+ * this also syncs the clump directory.
+ */
+static void
+sealarena(Arena *arena)
+{
+        arena->inqueue = 1;
+        backsumarena(arena);
+}
+
+void
+backsumarena(Arena *arena)
+{
+        ASum *as;
+
+        if(sumwait.l == nil)
+                return;
+
+        as = MK(ASum);
+        if(as == nil)
+                return;
+        qlock(&sumlock);
+        as->arena = arena;
+        as->next = sumq;
+        sumq = as;
+        rwakeup(&sumwait);
+        qunlock(&sumlock);
+}
+
+static void
+sumproc(void *unused)
+{
+        ASum *as;
+        Arena *arena;
+
+        USED(unused);
+
+        for(;;){
+                qlock(&sumlock);
+                while(sumq == nil)
+                        rsleep(&sumwait);
+                as = sumq;
+                sumq = as->next;
+                qunlock(&sumlock);
+                arena = as->arena;
+                free(as);
+
+                sumarena(arena);
+        }
+}
+
+void
+sumarena(Arena *arena)
+{
+        ZBlock *b;
+        DigestState s;
+        u64int a, e;
+        u32int bs;
+        u8int score[VtScoreSize];
+
+        bs = MaxIoSize;
+        if(bs < arena->blocksize)
+                bs = arena->blocksize;
+
+        /*
+         * read & sum all blocks except the last one
+         */
+        memset(&s, 0, sizeof s);
+        b = alloczblock(bs, 0, arena->part->blocksize);
+        e = arena->base + arena->size;
+        for(a = arena->base - arena->blocksize; a + arena->blocksize <= e; a += bs){
+                sleep(arenasumsleeptime);
+                if(a + bs > e)
+                        bs = arena->blocksize;
+                if(readpart(arena->part, a, b->data, bs) < 0)
+                        goto ReadErr;
+                addstat(StatSumRead, 1);
+                addstat(StatSumReadBytes, bs);
+                sha1(b->data, bs, nil, &s);
+        }
+
+        /*
+         * the last one is special, since it may already have the checksum included
+         */
+        bs = arena->blocksize;
+        if(readpart(arena->part, e, b->data, bs) < 0){
+ReadErr:
+                logerr(EOk, "sumarena can't sum %s, read at %lld failed: %r", arena->name, a);
+                freezblock(b);
+                return;
+        }
+        addstat(StatSumRead, 1);
+        addstat(StatSumReadBytes, bs);
+
+        sha1(b->data, bs-VtScoreSize, nil, &s);
+        sha1(zeroscore, VtScoreSize, nil, &s);
+        sha1(nil, 0, score, &s);
+
+        /*
+         * check for no checksum or the same
+         *
+         * the writepart is okay because we flushed the dcache in sealarena
+         */
+        if(scorecmp(score, &b->data[bs - VtScoreSize]) != 0){
+                if(scorecmp(zeroscore, &b->data[bs - VtScoreSize]) != 0)
+                        logerr(EOk, "overwriting mismatched checksums for arena=%s, found=%V calculated=%V",
+                                arena->name, &b->data[bs - VtScoreSize], score);
+                scorecp(&b->data[bs - VtScoreSize], score);
+                if(writepart(arena->part, e, b->data, bs) < 0)
+                        logerr(EOk, "sumarena can't write sum for %s: %r", arena->name);
+        }
+        freezblock(b);
+
+        qlock(&arena->lock);
+        scorecp(arena->score, score);
+        qunlock(&arena->lock);
+}
+
+/*
+ * write the arena trailer block to the partition
+ */
+int
+wbarena(Arena *arena)
+{
+        DBlock *b;
+        int bad;
+
+        if((b = getdblock(arena->part, arena->base + arena->size, OWRITE)) == nil){
+                logerr(EAdmin, "can't write arena trailer: %r");
+                return -1;
+        }
+        dirtydblock(b, DirtyArenaTrailer);
+        bad = okarena(arena)<0 || packarena(arena, b->data)<0;
+        putdblock(b);
+        if(bad)
+                return -1;
+        return 0;
+}
+
+int
+wbarenahead(Arena *arena)
+{
+        ZBlock *b;
+        ArenaHead head;
+        int bad;
+
+        namecp(head.name, arena->name);
+        head.version = arena->version;
+        head.size = arena->size + 2 * arena->blocksize;
+        head.blocksize = arena->blocksize;
+        head.clumpmagic = arena->clumpmagic;
+        b = alloczblock(arena->blocksize, 1, arena->part->blocksize);
+        if(b == nil){
+                logerr(EAdmin, "can't write arena header: %r");
+///ZZZ add error message?
+                return -1;
+        }
+        /*
+         * this writepart is okay because it only happens
+         * during initialization.
+         */
+        bad = packarenahead(&head, b->data)<0 ||
+              writepart(arena->part, arena->base - arena->blocksize, b->data, arena->blocksize)<0;
+        freezblock(b);
+        if(bad)
+                return -1;
+        return 0;
+}
+
+/*
+ * read the arena header and trailer blocks from disk
+ */
+static int
+loadarena(Arena *arena)
+{
+        ArenaHead head;
+        ZBlock *b;
+
+        b = alloczblock(arena->blocksize, 0, arena->part->blocksize);
+        if(b == nil)
+                return -1;
+        if(readpart(arena->part, arena->base + arena->size, b->data, arena->blocksize) < 0){
+                freezblock(b);
+                return -1;
+        }
+        if(unpackarena(arena, b->data) < 0){
+                freezblock(b);
+                return -1;
+        }
+        if(arena->version != ArenaVersion4 && arena->version != ArenaVersion5){
+                seterr(EAdmin, "unknown arena version %d", arena->version);
+                freezblock(b);
+                return -1;
+        }
+        scorecp(arena->score, &b->data[arena->blocksize - VtScoreSize]);
+
+        if(readpart(arena->part, arena->base - arena->blocksize, b->data, arena->blocksize) < 0){
+                logerr(EAdmin, "can't read arena header: %r");
+                freezblock(b);
+                return 0;
+        }
+        if(unpackarenahead(&head, b->data) < 0)
+                logerr(ECorrupt, "corrupted arena header: %r");
+        else if(namecmp(arena->name, head.name)!=0
+             || arena->clumpmagic != head.clumpmagic
+             || arena->version != head.version
+             || arena->blocksize != head.blocksize
+             || arena->size + 2 * arena->blocksize != head.size){
+                if(namecmp(arena->name, head.name)!=0)
+                        logerr(ECorrupt, "arena tail name %s head %s", 
+                                arena->name, head.name);
+                else if(arena->clumpmagic != head.clumpmagic)
+                        logerr(ECorrupt, "arena tail clumpmagic 0x%lux head 0x%lux",
+                                (ulong)arena->clumpmagic, (ulong)head.clumpmagic);
+                else if(arena->version != head.version)
+                        logerr(ECorrupt, "arena tail version %d head version %d",
+                                arena->version, head.version);
+                else if(arena->blocksize != head.blocksize)
+                        logerr(ECorrupt, "arena tail block size %d head %d",
+                                arena->blocksize, head.blocksize);
+                else if(arena->size+2*arena->blocksize != head.size)
+                        logerr(ECorrupt, "arena tail size %lud head %lud",
+                                (ulong)arena->size+2*arena->blocksize, head.size);
+                else
+                        logerr(ECorrupt, "arena header inconsistent with arena data");
+        }
+        freezblock(b);
+
+        return 0;
+}
+
+static int
+okarena(Arena *arena)
+{
+        u64int dsize;
+        int ok;
+
+        ok = 0;
+        dsize = arenadirsize(arena, arena->diskstats.clumps);
+        if(arena->diskstats.used + dsize > arena->size){
+                seterr(ECorrupt, "arena used > size");
+                ok = -1;
+        }
+
+        if(arena->diskstats.cclumps > arena->diskstats.clumps)
+                logerr(ECorrupt, "arena has more compressed clumps than total clumps");
+
+        if(arena->diskstats.uncsize + arena->diskstats.clumps * ClumpSize + arena->blocksize < arena->diskstats.used)
+                logerr(ECorrupt, "arena uncompressed size inconsistent with used space %lld %d %lld", arena->diskstats.uncsize, arena->diskstats.clumps, arena->diskstats.used);
+
+        if(arena->ctime > arena->wtime)
+                logerr(ECorrupt, "arena creation time after last write time");
+
+        return ok;
+}
+
+static CIBlock*
+getcib(Arena *arena, int clump, int writing, CIBlock *rock)
+{
+        int mode;
+        CIBlock *cib;
+        u32int block, off;
+
+        if(clump >= arena->memstats.clumps){
+                seterr(EOk, "clump directory access out of range");
+                return nil;
+        }
+        block = clump / arena->clumpmax;
+        off = (clump - block * arena->clumpmax) * ClumpInfoSize;
+        cib = rock;
+        cib->block = block;
+        cib->offset = off;
+
+        if(writing){
+                if(off == 0 && clump == arena->memstats.clumps-1)
+                        mode = OWRITE;
+                else
+                        mode = ORDWR;
+        }else
+                mode = OREAD;
+
+        cib->data = getdblock(arena->part,
+                arena->base + arena->size - (block + 1) * arena->blocksize, mode);
+        if(cib->data == nil)
+                return nil;
+        return cib;
+}
+
+static void
+putcib(Arena *arena, CIBlock *cib)
+{
+        putdblock(cib->data);
+        cib->data = nil;
+}
diff --git a/src/cmd/venti/srv/arenas.c b/src/cmd/venti/srv/arenas.c
t@@ -0,0 +1,414 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+typedef struct AHash        AHash;
+
+/*
+ * hash table for finding arena's based on their names.
+ */
+struct AHash
+{
+        AHash        *next;
+        Arena        *arena;
+};
+
+enum
+{
+        AHashSize        = 512
+};
+
+static AHash        *ahash[AHashSize];
+
+static u32int
+hashstr(char *s)
+{
+        u32int h;
+        int c;
+
+        h = 0;
+        for(; c = *s; s++){
+                c ^= c << 6;
+                h += (c << 11) ^ (c >> 1);
+                c = *s;
+                h ^= (c << 14) + (c << 7) + (c << 4) + c;
+        }
+        return h;
+}
+
+int
+addarena(Arena *arena)
+{
+        AHash *a;
+        u32int h;
+
+        h = hashstr(arena->name) & (AHashSize - 1);
+        a = MK(AHash);
+        if(a == nil)
+                return -1;
+        a->arena = arena;
+        a->next = ahash[h];
+        ahash[h] = a;
+        return 0;
+}
+
+Arena*
+findarena(char *name)
+{
+        AHash *a;
+        u32int h;
+
+        h = hashstr(name) & (AHashSize - 1);
+        for(a = ahash[h]; a != nil; a = a->next)
+                if(strcmp(a->arena->name, name) == 0)
+                        return a->arena;
+        return nil;
+}
+
+int
+delarena(Arena *arena)
+{
+        AHash *a, *last;
+        u32int h;
+
+        h = hashstr(arena->name) & (AHashSize - 1);
+        last = nil;
+        for(a = ahash[h]; a != nil; a = a->next){
+                if(a->arena == arena){
+                        if(last != nil)
+                                last->next = a->next;
+                        else
+                                ahash[h] = a->next;
+                        free(a);
+                        return 0;
+                }
+                last = a;
+        }
+        return -1;
+}
+
+ArenaPart*
+initarenapart(Part *part)
+{
+        AMapN amn;
+        ArenaPart *ap;
+        ZBlock *b;
+        u32int i;
+        int ok;
+
+        b = alloczblock(HeadSize, 0, 0);
+        if(b == nil || readpart(part, PartBlank, b->data, HeadSize) < 0){
+                seterr(EAdmin, "can't read arena partition header: %r");
+                return nil;
+        }
+
+        ap = MKZ(ArenaPart);
+        if(ap == nil){
+                freezblock(b);
+                return nil;
+        }
+        ap->part = part;
+        ok = unpackarenapart(ap, b->data);
+        freezblock(b);
+        if(ok < 0){
+                freearenapart(ap, 0);
+                return nil;
+        }
+
+        ap->tabbase = (PartBlank + HeadSize + ap->blocksize - 1) & ~(ap->blocksize - 1);
+        if(ap->version != ArenaPartVersion){
+                seterr(ECorrupt, "unknown arena partition version %d", ap->version);
+                freearenapart(ap, 0);
+                return nil;
+        }
+        if(ap->blocksize & (ap->blocksize - 1)){
+                seterr(ECorrupt, "illegal non-power-of-2 block size %d\n", ap->blocksize);
+                freearenapart(ap, 0);
+                return nil;
+        }
+        if(ap->tabbase >= ap->arenabase){
+                seterr(ECorrupt, "arena partition table overlaps with arena storage");
+                freearenapart(ap, 0);
+                return nil;
+        }
+        ap->tabsize = ap->arenabase - ap->tabbase;
+        partblocksize(part, ap->blocksize);
+        ap->size = ap->part->size & ~(u64int)(ap->blocksize - 1);
+
+        if(readarenamap(&amn, part, ap->tabbase, ap->tabsize) < 0){
+                freearenapart(ap, 0);
+                return nil;
+        }
+        ap->narenas = amn.n;
+        ap->map = amn.map;
+        if(okamap(ap->map, ap->narenas, ap->arenabase, ap->size, "arena table") < 0){
+                freearenapart(ap, 0);
+                return nil;
+        }
+
+        ap->arenas = MKNZ(Arena*, ap->narenas);
+        for(i = 0; i < ap->narenas; i++){
+                ap->arenas[i] = initarena(part, ap->map[i].start, ap->map[i].stop - ap->map[i].start, ap->blocksize);
+                if(ap->arenas[i] == nil){
+                        seterr(ECorrupt, "%s: %r", ap->map[i].name);
+                        freearenapart(ap, 1);
+                        return nil;
+                }
+                if(namecmp(ap->map[i].name, ap->arenas[i]->name) != 0){
+                        seterr(ECorrupt, "arena name mismatches with expected name: %s vs. %s",
+                                ap->map[i].name, ap->arenas[i]->name);
+                        freearenapart(ap, 1);
+                        return nil;
+                }
+                if(findarena(ap->arenas[i]->name)){
+                        seterr(ECorrupt, "duplicate arena name %s in %s",
+                                ap->map[i].name, ap->part->name);
+                        freearenapart(ap, 1);
+                        return nil;
+                }
+        }
+
+        for(i = 0; i < ap->narenas; i++)
+                addarena(ap->arenas[i]);
+
+        return ap;
+}
+
+ArenaPart*
+newarenapart(Part *part, u32int blocksize, u32int tabsize)
+{
+        ArenaPart *ap;
+
+        if(blocksize & (blocksize - 1)){
+                seterr(ECorrupt, "illegal non-power-of-2 block size %d\n", blocksize);
+                return nil;
+        }
+        ap = MKZ(ArenaPart);
+        if(ap == nil)
+                return nil;
+
+        ap->version = ArenaPartVersion;
+        ap->part = part;
+        ap->blocksize = blocksize;
+        partblocksize(part, blocksize);
+        ap->size = part->size & ~(u64int)(blocksize - 1);
+        ap->tabbase = (PartBlank + HeadSize + blocksize - 1) & ~(blocksize - 1);
+        ap->arenabase = (ap->tabbase + tabsize + blocksize - 1) & ~(blocksize - 1);
+        ap->tabsize = ap->arenabase - ap->tabbase;
+        ap->narenas = 0;
+
+        if(wbarenapart(ap) < 0){
+                freearenapart(ap, 0);
+                return nil;
+        }
+
+        return ap;
+}
+
+int
+wbarenapart(ArenaPart *ap)
+{
+        ZBlock *b;
+
+        if(okamap(ap->map, ap->narenas, ap->arenabase, ap->size, "arena table") < 0)
+                return -1;
+        b = alloczblock(HeadSize, 1, 0);
+        if(b == nil)
+//ZZZ set error message?
+                return -1;
+
+        if(packarenapart(ap, b->data) < 0){
+                seterr(ECorrupt, "can't make arena partition header: %r");
+                freezblock(b);
+                return -1;
+        }
+        if(writepart(ap->part, PartBlank, b->data, HeadSize) < 0){
+                seterr(EAdmin, "can't write arena partition header: %r");
+                freezblock(b);
+                return -1;
+        }
+        freezblock(b);
+
+        return wbarenamap(ap->map, ap->narenas, ap->part, ap->tabbase, ap->tabsize);
+}
+
+void
+freearenapart(ArenaPart *ap, int freearenas)
+{
+        int i;
+
+        if(ap == nil)
+                return;
+        if(freearenas){
+                for(i = 0; i < ap->narenas; i++){
+                        if(ap->arenas[i] == nil)
+                                continue;
+                        delarena(ap->arenas[i]);
+                        freearena(ap->arenas[i]);
+                }
+        }
+        free(ap->map);
+        free(ap->arenas);
+        free(ap);
+}
+
+int
+okamap(AMap *am, int n, u64int start, u64int stop, char *what)
+{
+        u64int last;
+        u32int i;
+
+        last = start;
+        for(i = 0; i < n; i++){
+                if(am[i].start < last){
+                        if(i == 0)
+                                seterr(ECorrupt, "invalid start address in %s", what);
+                        else
+                                seterr(ECorrupt, "overlapping ranges in %s", what);
+                        return -1;
+                }
+                if(am[i].stop < am[i].start){
+                        seterr(ECorrupt, "invalid range in %s", what);
+                        return -1;
+                }
+                last = am[i].stop;
+        }
+        if(last > stop){
+                seterr(ECorrupt, "invalid ending address in %s", what);
+                return -1;
+        }
+        return 0;
+}
+
+int
+maparenas(AMap *am, Arena **arenas, int n, char *what)
+{
+        u32int i;
+
+        for(i = 0; i < n; i++){
+                arenas[i] = findarena(am[i].name);
+                if(arenas[i] == nil){
+                        seterr(EAdmin, "can't find arena '%s' for '%s'\n", am[i].name, what);
+                        return -1;
+                }
+        }
+        return 0;
+}
+
+int
+readarenamap(AMapN *amn, Part *part, u64int base, u32int size)
+{
+        IFile f;
+        u32int ok;
+
+        if(partifile(&f, part, base, size) < 0)
+                return -1;
+        ok = parseamap(&f, amn);
+        freeifile(&f);
+        return ok;
+}
+
+int
+wbarenamap(AMap *am, int n, Part *part, u64int base, u64int size)
+{
+        Fmt f;
+        ZBlock *b;
+
+        b = alloczblock(size, 1, part->blocksize);
+        if(b == nil)
+                return -1;
+
+        fmtzbinit(&f, b);
+
+        if(outputamap(&f, am, n) < 0){
+                seterr(ECorrupt, "arena set size too small");
+                freezblock(b);
+                return -1;
+        }
+        if(writepart(part, base, b->data, size) < 0){
+                seterr(EAdmin, "can't write arena set: %r");
+                freezblock(b);
+                return -1;
+        }
+        freezblock(b);
+        return 0;
+}
+
+/*
+ * amap: n '\n' amapelem * n
+ * n: u32int
+ * amapelem: name '\t' astart '\t' asize '\n'
+ * astart, asize: u64int
+ */
+int
+parseamap(IFile *f, AMapN *amn)
+{
+        AMap *am;
+        u64int v64;
+        u32int v;
+        char *s, *t, *flds[4];
+        int i, n;
+
+        /*
+         * arenas
+         */
+        if(ifileu32int(f, &v) < 0){
+                seterr(ECorrupt, "syntax error: bad number of elements in %s", f->name);
+                return -1;
+        }
+        n = v;
+        if(n > MaxAMap){
+                seterr(ECorrupt, "illegal number of elements in %s", f->name);
+                return -1;
+        }
+        am = MKNZ(AMap, n);
+        if(am == nil){
+                fprint(2, "out of memory\n");
+                return -1;
+        }
+        for(i = 0; i < n; i++){
+                s = ifileline(f);
+                if(s)
+                        t = estrdup(s);
+                else
+                        t = nil;
+                if(s == nil || getfields(s, flds, 4, 0, "\t") != 3){
+                        fprint(2, "early eof after %d of %d, %s:#%d: %s\n", i, n, f->name, f->pos, t);
+                        free(t);
+                        return -1;
+                }
+                free(t);
+                if(nameok(flds[0]) < 0)
+                        return -1;
+                namecp(am[i].name, flds[0]);
+                if(stru64int(flds[1], &v64) < 0){
+                        seterr(ECorrupt, "syntax error: bad arena base address in %s", f->name);
+                        free(am);
+                        return -1;
+                }
+                am[i].start = v64;
+                if(stru64int(flds[2], &v64) < 0){
+                        seterr(ECorrupt, "syntax error: bad arena size in %s", f->name);
+                        free(am);
+                        return -1;
+                }
+                am[i].stop = v64;
+        }
+
+        amn->map = am;
+        amn->n = n;
+        return 0;
+}
+
+int
+outputamap(Fmt *f, AMap *am, int n)
+{
+        int i;
+
+        if(fmtprint(f, "%ud\n", n) < 0)
+                return -1;
+        for(i = 0; i < n; i++)
+                if(fmtprint(f, "%s\t%llud\t%llud\n", am[i].name, am[i].start, am[i].stop) < 0)
+                        return -1;
+        return 0;
+}
diff --git a/src/cmd/venti/srv/bloom.c b/src/cmd/venti/srv/bloom.c
t@@ -0,0 +1,210 @@
+/*
+ * Bloom filter tracking which scores are present in our arenas
+ * and (more importantly) which are not.  
+ */
+
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+int
+bloominit(Bloom *b, vlong vsize, u8int *data)
+{
+        ulong size;
+        
+        size = vsize;
+        if(size != vsize){        /* truncation */
+                werrstr("bloom data too big");
+                return -1;
+        }
+        
+        b->size = size;
+        b->nhash = 32;        /* will be fixed by caller on initialization */
+        if(data != nil)
+                if(unpackbloomhead(b, data) < 0)
+                        return -1;
+        
+fprint(2, "bloom size %lud nhash %d\n", b->size, b->nhash);
+        b->mask = b->size-1;
+        b->data = data;
+        return 0;
+}
+
+void
+wbbloomhead(Bloom *b)
+{
+        packbloomhead(b, b->data);
+}
+
+Bloom*
+readbloom(Part *p)
+{
+        int i, n;
+        uint ones;
+        uchar buf[512];
+        uchar *data;
+        u32int *a;
+        Bloom *b;
+        
+        b = vtmallocz(sizeof *b);
+        if(readpart(p, 0, buf, sizeof buf) < 0)
+                return nil;
+fprint(2, "header %.16H\n", buf);
+        if(bloominit(b, 0, buf) < 0){
+                vtfree(b);
+                return nil;
+        }
+        data = vtmallocz(b->size);
+        if(readpart(p, 0, data, b->size) < 0){
+                vtfree(b);
+                vtfree(data);
+                return nil;
+        }
+        b->data = data;
+        b->part = p;
+
+        a = (u32int*)b->data;
+        n = b->size/4;
+        ones = 0;
+        for(i=0; isize == MaxBloomSize)        /* 2^32 overflows ulong */
+                addstat(StatBloomBits, b->size*8-1);
+        else
+                addstat(StatBloomBits, b->size*8);
+                
+        return b;
+}
+
+int
+writebloom(Bloom *b)
+{
+        wbbloomhead(b);
+        return writepart(b->part, 0, b->data, b->size);
+}
+
+/*
+ * Derive two random 32-bit quantities a, b from the score
+ * and then use a+b*i as a sequence of bloom filter indices.
+ * Michael Mitzenmacher has a recent (2005) paper saying this is okay.
+ * We reserve the bottom bytes (BloomHeadSize*8 bits) for the header.
+ */
+static void
+gethashes(u8int *score, ulong *h)
+{
+        int i;
+        u32int a, b;
+
+        a = 0;
+        b = 0;
+        for(i=4; i+8<=VtScoreSize; i+=8){
+                a ^= *(u32int*)(score+i);
+                b ^= *(u32int*)(score+i+4);
+        }
+        if(i+4 <= VtScoreSize)        /* 20 is not 4-aligned */
+                a ^= *(u32int*)(score+i);
+        for(i=0; idata;
+        for(i=0; inhash; i++){
+                x = h[i];
+                y = &tab[(x&b->mask)>>5];
+                z = 1<<(x&31);
+                if(!(*y&z)){
+                        nnew++;
+                        *y |= z;
+                }
+        }
+        if(nnew)
+                addstat(StatBloomOnes, nnew);
+
+        trace("markbloomfilter", "markbloomfilter exit");
+}
+
+static int
+_inbloomfilter(Bloom *b, u8int *score)
+{
+        int i;
+        ulong h[BloomMaxHash], x;
+        u32int *tab;
+
+        gethashes(score, h);
+        tab = (u32int*)b->data;
+        for(i=0; inhash; i++){
+                x = h[i];
+                if(!(tab[(x&b->mask)>>5] & (1<<(x&31))))
+                        return 0;
+        }
+        return 1;
+}
+
+int
+inbloomfilter(Bloom *b, u8int *score)
+{
+        int r;
+        uint ms;
+
+        if(b == nil)
+                return 1;
+
+        ms = msec();
+        rlock(&b->lk);
+        r = _inbloomfilter(b, score);
+        runlock(&b->lk);
+        ms = ms - msec();
+        addstat2(StatBloomLookup, 1, StatBloomLookupTime, ms);
+        if(r)
+                addstat(StatBloomMiss, 1);
+        else
+                addstat(StatBloomHit, 1);
+        return r;
+}
+
+void
+markbloomfilter(Bloom *b, u8int *score)
+{
+        if(b == nil)
+                return;
+
+        rlock(&b->lk);
+        qlock(&b->mod);
+        _markbloomfilter(b, score);
+        qunlock(&b->mod);
+        runlock(&b->lk);
+}
+
+static void
+bloomwriteproc(void *v)
+{
+        Bloom *b;
+        
+        b = v;
+        for(;;){
+                recv(b->writechan, 0);
+                if(writebloom(b) < 0)
+                        fprint(2, "oops! writing bloom: %r\n");
+                send(b->writedonechan, 0);
+        }
+}
+
+void
+startbloomproc(Bloom *b)
+{
+        b->writechan = chancreate(sizeof(void*), 0);
+        b->writedonechan = chancreate(sizeof(void*), 0);
+        vtproc(bloomwriteproc, b);        
+}
diff --git a/src/cmd/venti/srv/buildbuck.c b/src/cmd/venti/srv/buildbuck.c
t@@ -0,0 +1,132 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+/*
+ * An IEStream is a sorted list of index entries.
+ */
+struct IEStream
+{
+        Part        *part;
+        u64int        off;                /* read position within part */
+        u64int        n;                /* number of valid ientries left to read */
+        u32int        size;                /* allocated space in buffer */
+        u8int        *buf;
+        u8int        *pos;                /* current place in buffer */
+        u8int        *epos;                /* end of valid buffer contents */
+};
+
+IEStream*
+initiestream(Part *part, u64int off, u64int clumps, u32int size)
+{
+        IEStream *ies;
+
+//ZZZ out of memory?
+        ies = MKZ(IEStream);
+        ies->buf = MKN(u8int, size);
+        ies->epos = ies->buf;
+        ies->pos = ies->epos;
+        ies->off = off;
+        ies->n = clumps;
+        ies->size = size;
+        ies->part = part;
+        return ies;
+}
+
+void
+freeiestream(IEStream *ies)
+{
+        if(ies == nil)
+                return;
+        free(ies->buf);
+        free(ies);
+}
+
+/*
+ * Return the next IEntry (still packed) in the stream.
+ */
+static u8int*
+peekientry(IEStream *ies)
+{
+        u32int n, nn;
+
+        n = ies->epos - ies->pos;
+        if(n < IEntrySize){
+                memmove(ies->buf, ies->pos, n);
+                ies->epos = &ies->buf[n];
+                ies->pos = ies->buf;
+                nn = ies->size;
+                if(nn > ies->n * IEntrySize)
+                        nn = ies->n * IEntrySize;
+                nn -= n;
+                if(nn == 0)
+                        return nil;
+//fprint(2, "peek %d from %llud into %p\n", nn, ies->off, ies->epos);
+                if(readpart(ies->part, ies->off, ies->epos, nn) < 0){
+                        seterr(EOk, "can't read sorted index entries: %r");
+                        return nil;
+                }
+                ies->epos += nn;
+                ies->off += nn;
+        }
+        return ies->pos;
+}
+
+/*
+ * Compute the bucket number for the given IEntry.
+ * Knows that the score is the first thing in the packed
+ * representation.
+ */
+static u32int
+iebuck(Index *ix, u8int *b, IBucket *ib, IEStream *ies)
+{
+        USED(ies);
+        USED(ib);
+        return hashbits(b, 32) / ix->div;
+}
+
+/*
+ * Fill ib with the next bucket in the stream.
+ */
+u32int
+buildbucket(Index *ix, IEStream *ies, IBucket *ib, uint maxdata)
+{
+        IEntry ie1, ie2;
+        u8int *b;
+        u32int buck;
+
+        buck = TWID32;
+        ib->n = 0;
+        while(ies->n){
+                b = peekientry(ies);
+                if(b == nil)
+                        return TWID32;
+//fprint(2, "b=%p ies->n=%lld ib.n=%d buck=%d score=%V\n", b, ies->n, ib->n, iebuck(ix, b, ib, ies), b);
+                if(ib->n == 0)
+                        buck = iebuck(ix, b, ib, ies);
+                else{
+                        if(buck != iebuck(ix, b, ib, ies))
+                                break;
+                        if(ientrycmp(&ib->data[(ib->n - 1)* IEntrySize], b) == 0){
+                                /*
+                                 * guess that the larger address is the correct one to use
+                                 */
+                                unpackientry(&ie1, &ib->data[(ib->n - 1)* IEntrySize]);
+                                unpackientry(&ie2, b);
+                                seterr(EOk, "duplicate index entry for score=%V type=%d", ie1.score, ie1.ia.type);
+                                ib->n--;
+                                if(ie1.ia.addr > ie2.ia.addr)
+                                        memmove(b, &ib->data[ib->n * IEntrySize], IEntrySize);
+                        }
+                }
+                if((ib->n+1)*IEntrySize > maxdata){
+                        seterr(EOk, "bucket overflow");
+                        return TWID32;
+                }
+                memmove(&ib->data[ib->n * IEntrySize], b, IEntrySize);
+                ib->n++;
+                ies->n--;
+                ies->pos += IEntrySize;
+        }
+        return buck;
+}
diff --git a/src/cmd/venti/srv/buildindex.c b/src/cmd/venti/srv/buildindex.c
t@@ -0,0 +1,160 @@
+/*
+ * Rebuild the Venti index from scratch.
+ */
+
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+/*
+ * Write a single bucket.  Could profit from a big buffer here
+ * so that we can absorb sporadic runs of blocks into one write,
+ * avoiding disk seeks.
+ */
+static int
+writebucket(Index *ix, u32int buck, IBucket *ib, ZBlock *b)
+{
+        ISect *is;
+
+        is = ix->sects[indexsect0(ix, buck)];
+        if(buck < is->start || buck >= is->stop){
+                seterr(EAdmin, "cannot find index section for bucket %lud\n", (ulong)buck);
+                return -1;
+        }
+        buck -= is->start;
+
+/*
+        qlock(&stats.lock);
+        stats.indexwrites++;
+        qunlock(&stats.lock);
+*/
+        packibucket(ib, b->data, is->bucketmagic);
+        return writepart(is->part, is->blockbase + ((u64int)buck << is->blocklog), b->data, is->blocksize);
+}
+
+static int
+buildindex(Index *ix, Part *part, u64int off, u64int clumps, int zero)
+{
+        IEStream *ies;
+        IBucket ib, zib;
+        ZBlock *z, *b;
+        u32int next, buck;
+        int ok;
+        uint nbuck;
+        u64int found = 0;
+
+//ZZZ make buffer size configurable
+        b = alloczblock(ix->blocksize, 0, ix->blocksize);
+        z = alloczblock(ix->blocksize, 1, ix->blocksize);
+        ies = initiestream(part, off, clumps, 64*1024);
+        if(b == nil || z == nil || ies == nil){
+                ok = 0;
+                goto breakout;
+                return -1;
+        }
+        ok = 0;
+        next = 0;
+        memset(&ib, 0, sizeof ib);
+        ib.data = b->data + IBucketSize;
+        zib.data = z->data + IBucketSize;
+        zib.n = 0;
+        nbuck = 0;
+        for(;;){
+                buck = buildbucket(ix, ies, &ib, ix->blocksize-IBucketSize);
+                found += ib.n;
+                if(zero){
+                        for(; next != buck; next++){
+                                if(next == ix->buckets){
+                                        if(buck != TWID32){
+                                                fprint(2, "bucket out of range\n");
+                                                ok = -1;
+                                        }
+                                        goto breakout;
+                                }
+                                if(writebucket(ix, next, &zib, z) < 0){
+                                        fprint(2, "can't write zero bucket to buck=%d: %r", next);
+                                        ok = -1;
+                                }
+                        }
+                }
+                if(buck >= ix->buckets){
+                        if(buck == TWID32)
+                                break;
+                        fprint(2, "bucket out of range\n");
+                        ok = -1;
+                        goto breakout;
+                }
+                if(writebucket(ix, buck, &ib, b) < 0){
+                        fprint(2, "bad bucket found=%lld: %r\n", found);
+                        ok = -1;
+                }
+                next = buck + 1;
+                if(++nbuck%10000 == 0)
+                        fprint(2, "\t%,d buckets written...\n", nbuck);
+        }
+breakout:;
+        fprint(2, "wrote index with %lld entries\n", found);
+        freeiestream(ies);
+        freezblock(z);
+        freezblock(b);
+        return ok;
+}
+
+void
+usage(void)
+{
+        fprint(2, "usage: buildindex [-Z] [-B blockcachesize] config tmppart\n");
+        threadexitsall(0);
+}
+
+Config conf;
+
+void
+threadmain(int argc, char *argv[])
+{
+        Part *part;
+        u64int clumps, base;
+        u32int bcmem;
+        int zero;
+
+        zero = 1;
+        bcmem = 0;
+        ARGBEGIN{
+        case 'B':
+                bcmem = unittoull(ARGF());
+                break;
+        case 'Z':
+                zero = 0;
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        if(argc != 2)
+                usage();
+
+        if(initventi(argv[0], &conf) < 0)
+                sysfatal("can't init venti: %r");
+
+        if(bcmem < maxblocksize * (mainindex->narenas + mainindex->nsects * 4 + 16))
+                bcmem = maxblocksize * (mainindex->narenas + mainindex->nsects * 4 + 16);
+        if(0) fprint(2, "initialize %d bytes of disk block cache\n", bcmem);
+        initdcache(bcmem);
+
+        fprint(2, "building a new index %s using %s for temporary storage\n", mainindex->name, argv[1]);
+
+        part = initpart(argv[1], ORDWR|ODIRECT);
+        if(part == nil)
+                sysfatal("can't initialize temporary partition: %r");
+
+        clumps = sortrawientries(mainindex, part, &base, mainindex->bloom);
+        if(clumps == TWID64)
+                sysfatal("can't build sorted index: %r");
+        fprint(2, "found and sorted index entries for clumps=%lld at %lld\n", clumps, base);
+
+        if(buildindex(mainindex, part, base, clumps, zero) < 0)
+                sysfatal("can't build new index: %r");
+        
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/srv/checkarenas.c b/src/cmd/venti/srv/checkarenas.c
t@@ -0,0 +1,135 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+static int        verbose;
+
+static void
+checkarena(Arena *arena, int scan, int fix)
+{
+        ATailStats old;
+        int err, e;
+
+        if(verbose && arena->memstats.clumps)
+                printarena(2, arena);
+
+        old = arena->memstats;
+
+        if(scan){
+                arena->memstats.used = 0;
+                arena->memstats.clumps = 0;
+                arena->memstats.cclumps = 0;
+                arena->memstats.uncsize = 0;
+        }
+
+        err = 0;
+        for(;;){
+                e = syncarena(arena, 0, 1000, 0, fix);
+                err |= e;
+                if(!(e & SyncHeader))
+                        break;
+                if(verbose && arena->memstats.clumps)
+                        fprint(2, ".");
+        }
+        if(verbose && arena->memstats.clumps)
+                fprint(2, "\n");
+
+        err &= ~SyncHeader;
+        if(arena->memstats.used != old.used
+        || arena->memstats.clumps != old.clumps
+        || arena->memstats.cclumps != old.cclumps
+        || arena->memstats.uncsize != old.uncsize){
+                fprint(2, "%s: incorrect arena header fields\n", arena->name);
+                printarena(2, arena);
+                err |= SyncHeader;
+        }
+
+        if(!err || !fix)
+                return;
+
+        fprint(2, "%s: writing fixed arena header fields\n", arena->name);
+        arena->diskstats = arena->memstats;
+        if(wbarena(arena) < 0)
+                fprint(2, "arena header write failed: %r\n");
+        flushdcache();
+}
+
+void
+usage(void)
+{
+        fprint(2, "usage: checkarenas [-afv] file [arenaname...]\n");
+        threadexitsall(0);
+}
+
+int
+should(char *name, int argc, char **argv)
+{
+        int i;
+
+        if(argc == 0)
+                return 1;
+        for(i=0; i 1){
+                printarenapart(2, ap);
+                fprint(2, "\n");
+        }
+
+        initdcache(8 * MaxDiskBlock);
+
+        for(i = 0; i < ap->narenas; i++)
+                if(should(ap->arenas[i]->name, argc, argv))
+                        checkarena(ap->arenas[i], scan, fix);
+
+        if(verbose > 1)
+                printstats();
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/srv/checkindex.c b/src/cmd/venti/srv/checkindex.c
t@@ -0,0 +1,293 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+static int extra, missing, wrong;
+
+static void
+phdr(DBlock *eb)
+{
+        static int did;
+        
+        if(!did){
+                did = 1;
+                print("# diff actual correct\n");
+        }
+        print("%s block 0x%llux\n", eb->part->name, eb->addr);
+}
+
+static void
+pie(IEntry *ie, char c)
+{
+        print("%c %V %22lld %3d %5d %3d\n",
+                c, ie->score, ie->ia.addr, ie->ia.type, ie->ia.size, ie->ia.blocks);
+}
+
+static int
+checkbucket(Index *ix, u32int buck, IBucket *ib)
+{
+        ISect *is;
+        DBlock *eb;
+        IBucket eib;
+        IEntry ie, eie;
+        int i, ei, ok, c, hdr;
+
+        is = ix->sects[indexsect0(ix, buck)];
+        if(buck < is->start || buck >= is->stop){
+                seterr(EAdmin, "cannot find index section for bucket %lud\n", (ulong)buck);
+                return -1;
+        }
+        buck -= is->start;
+        eb = getdblock(is->part, is->blockbase + ((u64int)buck << is->blocklog), OREAD);
+        if(eb == nil)
+                return -1;
+        unpackibucket(&eib, eb->data, is->bucketmagic);
+
+        ok = 0;
+        ei = 0;
+        hdr = 0;
+        for(i = 0; i < ib->n; i++){
+                while(ei < eib.n){
+                        c = ientrycmp(&ib->data[i * IEntrySize], &eib.data[ei * IEntrySize]);
+                        if(c == 0){
+                                unpackientry(&ie, &ib->data[i * IEntrySize]);
+                                unpackientry(&eie, &eib.data[ei * IEntrySize]);
+                                if(iaddrcmp(&ie.ia, &eie.ia) != 0){
+                                        if(!hdr){
+                                                phdr(eb);
+                                                hdr = 1;
+                                        }
+                                        wrong++;
+                                        pie(&eie, '<');
+                                        pie(&ie, '>');
+                                }
+                                ei++;
+                                goto cont;
+                        }
+                        if(c < 0)
+                                break;
+                        if(!hdr){
+                                phdr(eb);
+                                hdr = 1;
+                        }
+                        unpackientry(&eie, &eib.data[ei*IEntrySize]);
+                        extra++;
+                        pie(&eie, '<');
+                        ei++;
+                        ok = -1;
+                }
+                if(!hdr){
+                        phdr(eb);
+                        hdr = 1;
+                }
+                unpackientry(&ie, &ib->data[i*IEntrySize]);
+                missing++;
+                pie(&ie, '>');
+                ok = -1;
+        cont:;
+        }
+        for(; ei < eib.n; ei++){
+                if(!hdr){
+                        phdr(eb);
+                        hdr = 1;
+                }
+                unpackientry(&eie, &eib.data[ei*IEntrySize]);
+                pie(&eie, '<');
+                ok = -1;
+        }
+        putdblock(eb);
+        return ok;
+}
+
+int
+checkindex(Index *ix, Part *part, u64int off, u64int clumps, int zero)
+{
+        IEStream *ies;
+        IBucket ib, zib;
+        ZBlock *z, *b;
+        u32int next, buck;
+        int ok, bok;
+u64int found = 0;
+
+//ZZZ make buffer size configurable
+        b = alloczblock(ix->blocksize, 0, ix->blocksize);
+        z = alloczblock(ix->blocksize, 1, ix->blocksize);
+        ies = initiestream(part, off, clumps, 64*1024);
+        if(b == nil || z == nil || ies == nil){
+                werrstr("allocating: %r");
+                ok = -1;
+                goto breakout;
+                return -1;
+        }
+        ok = 0;
+        next = 0;
+        memset(&ib, 0, sizeof ib);
+        ib.data = b->data;
+        zib.data = z->data;
+        zib.n = 0;
+        zib.buck = 0;
+        for(;;){
+                buck = buildbucket(ix, ies, &ib, ix->blocksize-IBucketSize);
+                found += ib.n;
+                if(zero){
+                        for(; next != buck; next++){
+                                if(next == ix->buckets){
+                                        if(buck != TWID32){
+                                                ok = -1;
+                                                werrstr("internal error: bucket out of range");
+                                        }
+                                        if(ok < 0)
+                                                werrstr("%d spurious entries, %d missing, %d wrong", extra, missing, wrong);
+                                        goto breakout;
+                                }
+                                bok = checkbucket(ix, next, &zib);
+                                if(bok < 0)
+                                        ok = -1;
+                        }
+                }
+                if(buck >= ix->buckets){
+                        if(buck == TWID32)
+                                break;
+                        werrstr("internal error: bucket out of range");
+                        ok = -1;
+                        goto breakout;
+                }
+                bok = checkbucket(ix, buck, &ib);
+                if(bok < 0)
+                        ok = -1;
+                next = buck + 1;
+        }
+breakout:
+        freeiestream(ies);
+        freezblock(z);
+        freezblock(b);
+        return ok;
+}
+
+int
+checkbloom(Bloom *b1, Bloom *b2, int fix)
+{
+        u32int *a1, *a2;
+        int i, n, extra, missing;
+        
+        if(b1==nil && b2==nil)
+                return 0;
+        if(b1==nil || b2==nil){
+                werrstr("nil/non-nil");
+                return -1;
+        }
+        wbbloomhead(b1);
+        wbbloomhead(b2);
+        if(memcmp(b1->data, b2->data, BloomHeadSize) != 0){
+                werrstr("bloom header mismatch");
+                return -1;
+        }
+        a1 = (u32int*)b1->data;
+        a2 = (u32int*)b2->data;
+        n = b1->size/4;
+        extra = 0;
+        missing = 0;
+        for(i=BloomHeadSize/4; idata, b2->data, b1->size);
+                return writebloom(b1);
+        }
+        return 0;
+}
+
+
+void
+usage(void)
+{
+        fprint(2, "usage: checkindex [-f] [-B blockcachesize] config tmp\n");
+        threadexitsall(0);
+}
+
+Config conf;
+
+void
+threadmain(int argc, char *argv[])
+{
+        Bloom *oldbloom, *newbloom;
+        Part *part;
+        u64int clumps, base;
+        u32int bcmem;
+        int fix, skipz, ok;
+
+        fix = 0;
+        bcmem = 0;
+        skipz = 0;
+        ARGBEGIN{
+        case 'B':
+                bcmem = unittoull(ARGF());
+                break;
+        case 'f':
+                fix++;
+                break;
+        case 'Z':
+                skipz = 1;
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        if(argc != 2)
+                usage();
+
+        ventifmtinstall();
+
+        part = initpart(argv[1], ORDWR|ODIRECT);
+        if(part == nil)
+                sysfatal("can't initialize temporary partition: %r");
+
+        if(!fix)
+                readonly = 1;
+
+        if(initventi(argv[0], &conf) < 0)
+                sysfatal("can't init venti: %r");
+        oldbloom = mainindex->bloom;
+        newbloom = nil;
+        if(oldbloom){
+                newbloom = vtmallocz(sizeof *newbloom);
+                bloominit(newbloom, oldbloom->size, nil);
+                newbloom->data = vtmallocz(oldbloom->size);
+        }
+        if(bcmem < maxblocksize * (mainindex->narenas + mainindex->nsects * 4 + 16))
+                bcmem = maxblocksize * (mainindex->narenas + mainindex->nsects * 4 + 16);
+        if(0) fprint(2, "initialize %d bytes of disk block cache\n", bcmem);
+        initdcache(bcmem);
+
+        fprint(2, "checkindex: building entry list\n");
+        clumps = sortrawientries(mainindex, part, &base, newbloom);
+        if(clumps == TWID64)
+                sysfatal("can't build sorted index: %r");
+        fprint(2, "checkindex: checking %lld entries at %lld\n", clumps, base);
+        ok = 0;
+        if(checkindex(mainindex, part, base, clumps, !skipz) < 0){
+                fprint(2, "checkindex: %r\n");
+                ok = -1;
+        }
+        if(checkbloom(oldbloom, newbloom, fix) < 0){
+                fprint(2, "checkbloom: %r\n");
+                ok = -1;
+        }
+        if(ok < 0)
+                sysfatal("errors found");
+        fprint(2, "checkindex: index is correct\n");
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/srv/clump.c b/src/cmd/venti/srv/clump.c
t@@ -0,0 +1,222 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+#include "whack.h"
+
+/*
+ * Write a lump to disk.  Updates ia with an index address
+ * for the newly-written lump.  Upon return, the lump will
+ * have been placed in the disk cache but will likely not be on disk yet.
+ */
+int
+storeclump(Index *ix, ZBlock *zb, u8int *sc, int type, u32int creator, IAddr *ia)
+{
+        ZBlock *cb;
+        Clump cl;
+        u64int a;
+        u8int bh[VtScoreSize];
+        int size, dsize;
+
+        trace(TraceLump, "storeclump enter", sc, type);
+        size = zb->len;
+        if(size > VtMaxLumpSize){
+                seterr(EStrange, "lump too large");
+                return -1;
+        }
+        if(vttypevalid(type) < 0){
+                seterr(EStrange, "invalid lump type");
+                return -1;
+        }
+
+        if(0){
+                scoremem(bh, zb->data, size);
+                if(scorecmp(sc, bh) != 0){
+                        seterr(ECorrupt, "storing clump: corrupted; expected=%V got=%V, size=%d", sc, bh, size);
+                        return -1;
+                }
+        }
+
+        cb = alloczblock(size + ClumpSize + U32Size, 0, 0);
+        if(cb == nil)
+                return -1;
+
+        cl.info.type = type;
+        cl.info.uncsize = size;
+        cl.creator = creator;
+        cl.time = now();
+        scorecp(cl.info.score, sc);
+
+        trace(TraceLump, "storeclump whackblock");
+        dsize = whackblock(&cb->data[ClumpSize], zb->data, size);
+        if(dsize > 0 && dsize < size){
+                cl.encoding = ClumpECompress;
+        }else{
+                if(dsize > size){
+                        fprint(2, "whack error: dsize=%d size=%d\n", dsize, size);
+                        abort();
+                }
+                cl.encoding = ClumpENone;
+                dsize = size;
+                memmove(&cb->data[ClumpSize], zb->data, size);
+        }
+        memset(cb->data+ClumpSize+dsize, 0, 4);
+        cl.info.size = dsize;
+
+        ia->addr = 0;
+        ia->type = type;
+        ia->size = size;
+        ia->blocks = (dsize + ClumpSize + (1 << ABlockLog) - 1) >> ABlockLog;
+
+        a = writeiclump(ix, &cl, cb->data, &ia->addr);
+
+        trace(TraceLump, "storeclump exit %lld", a);
+
+        freezblock(cb);
+        if(a == TWID64)
+                return -1;
+
+/*
+        qlock(&stats.lock);
+        stats.clumpwrites++;
+        stats.clumpbwrites += size;
+        stats.clumpbcomp += dsize;
+        qunlock(&stats.lock);
+*/
+
+        return 0;
+}
+
+u32int
+clumpmagic(Arena *arena, u64int aa)
+{
+        u8int buf[U32Size];
+
+        if(readarena(arena, aa, buf, U32Size) < 0)
+                return TWID32;
+        return unpackmagic(buf);
+}
+
+/*
+ * fetch a block based at addr.
+ * score is filled in with the block's score.
+ * blocks is roughly the length of the clump on disk;
+ * if zero, the length is unknown.
+ */
+ZBlock*
+loadclump(Arena *arena, u64int aa, int blocks, Clump *cl, u8int *score, int verify)
+{
+        Unwhack uw;
+        ZBlock *zb, *cb;
+        u8int bh[VtScoreSize], *buf;
+        u32int n;
+        int nunc;
+
+/*
+        qlock(&stats.lock);
+        stats.clumpreads++;
+        qunlock(&stats.lock);
+*/
+
+        if(blocks <= 0)
+                blocks = 1;
+
+        trace(TraceLump, "loadclump enter");
+
+        cb = alloczblock(blocks << ABlockLog, 0, 0);
+        if(cb == nil)
+                return nil;
+        n = readarena(arena, aa, cb->data, blocks << ABlockLog);
+        if(n < ClumpSize){
+                if(n != 0)
+                        seterr(ECorrupt, "loadclump read less than a header");
+                freezblock(cb);
+                return nil;
+        }
+        trace(TraceLump, "loadclump unpack");
+        if(unpackclump(cl, cb->data, arena->clumpmagic) < 0){
+                seterr(ECorrupt, "loadclump %s %llud: %r", arena->name, aa);
+                freezblock(cb);
+                return nil;
+        }
+        n -= ClumpSize;
+        if(n < cl->info.size){
+                freezblock(cb);
+                n = cl->info.size;
+                cb = alloczblock(n, 0, 0);
+                if(cb == nil)
+                        return nil;
+                if(readarena(arena, aa + ClumpSize, cb->data, n) != n){
+                        seterr(ECorrupt, "loadclump read too little data");
+                        freezblock(cb);
+                        return nil;
+                }
+                buf = cb->data;
+        }else
+                buf = cb->data + ClumpSize;
+
+        scorecp(score, cl->info.score);
+
+        zb = alloczblock(cl->info.uncsize, 0, 0);
+        if(zb == nil){
+                freezblock(cb);
+                return nil;
+        }
+        switch(cl->encoding){
+        case ClumpECompress:
+                trace(TraceLump, "loadclump decompress");
+                unwhackinit(&uw);
+                nunc = unwhack(&uw, zb->data, cl->info.uncsize, buf, cl->info.size);
+                if(nunc != cl->info.uncsize){
+                        if(nunc < 0)
+                                seterr(ECorrupt, "decompression of %llud failed: %s", aa, uw.err);
+                        else
+                                seterr(ECorrupt, "decompression of %llud gave partial block: %d/%d\n", aa, nunc, cl->info.uncsize);
+                        freezblock(cb);
+                        freezblock(zb);
+                        return nil;
+                }
+                break;
+        case ClumpENone:
+                if(cl->info.size != cl->info.uncsize){
+                        seterr(ECorrupt, "loading clump: bad uncompressed size for uncompressed block %llud", aa);
+                        freezblock(cb);
+                        freezblock(zb);
+                        return nil;
+                }
+                scoremem(bh, buf, cl->info.uncsize);
+                if(scorecmp(cl->info.score, bh) != 0)
+                        seterr(ECorrupt, "pre-copy sha1 wrong at %s %llud: expected=%V got=%V", arena->name, aa, cl->info.score, bh);
+                memmove(zb->data, buf, cl->info.uncsize);
+                break;
+        default:
+                seterr(ECorrupt, "unknown encoding in loadlump %llud", aa);
+                freezblock(cb);
+                freezblock(zb);
+                return nil;
+        }
+        freezblock(cb);
+
+        if(verify){
+                trace(TraceLump, "loadclump verify");
+                scoremem(bh, zb->data, cl->info.uncsize);
+                if(scorecmp(cl->info.score, bh) != 0){
+                        seterr(ECorrupt, "loading clump: corrupted at %s %llud; expected=%V got=%V", arena->name, aa, cl->info.score, bh);
+                        freezblock(zb);
+                        return nil;
+                }
+                if(vttypevalid(cl->info.type) < 0){
+                        seterr(ECorrupt, "loading lump at %s %llud: invalid lump type %d", arena->name, aa, cl->info.type);
+                        freezblock(zb);
+                        return nil;
+                }
+        }
+
+        trace(TraceLump, "loadclump exit");
+/*
+        qlock(&stats.lock);
+        stats.clumpbreads += cl->info.size;
+        stats.clumpbuncomp += cl->info.uncsize;
+        qunlock(&stats.lock);
+*/
+        return zb;
+}
diff --git a/src/cmd/venti/srv/clumpstats.c b/src/cmd/venti/srv/clumpstats.c
t@@ -0,0 +1,127 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+int        count[VtMaxLumpSize][VtMaxType];
+Config conf;
+
+enum
+{
+        ClumpChunks        = 32*1024
+};
+
+static int
+readarenainfo(Arena *arena)
+{
+        ClumpInfo *ci, *cis;
+        u32int clump;
+        int i, n, ok;
+
+        if(arena->memstats.clumps)
+                fprint(2, "reading directory for arena=%s with %d entries\n", arena->name, arena->memstats.clumps);
+
+        cis = MKN(ClumpInfo, ClumpChunks);
+        ok = 0;
+        for(clump = 0; clump < arena->memstats.clumps; clump += n){
+                n = ClumpChunks;
+
+                if(n > arena->memstats.clumps - clump)
+                        n = arena->memstats.clumps - clump;
+
+                if((i=readclumpinfos(arena, clump, cis, n)) != n){
+                        seterr(EOk, "arena directory read failed %d not %d: %r", i, n);
+                        ok = -1;
+                        break;
+                }
+
+                for(i = 0; i < n; i++){
+                        ci = &cis[i];
+                        if(ci->type >= VtMaxType || ci->uncsize >= VtMaxLumpSize) {
+                                fprint(2, "bad clump: %d: type = %d: size = %d\n", clump+i, ci->type, ci->uncsize);
+                                continue;
+                        }
+                        count[ci->uncsize][ci->type]++;
+                }
+        }
+        free(cis);
+        if(ok < 0)
+                return TWID32;
+        return clump;
+}
+
+static void
+clumpstats(Index *ix)
+{
+        int ok;
+        ulong clumps, n;
+        int i, j, t;
+
+        ok = 0;
+        clumps = 0;
+        for(i = 0; i < ix->narenas; i++){
+                n = readarenainfo(ix->arenas[i]);
+                if(n == TWID32){
+                        ok = -1;
+                        break;
+                }
+                clumps += n;
+        }
+
+        if(ok < 0)
+                return;
+
+        print("clumps = %ld\n", clumps);
+        for(i=0; inarenas + mainindex->nsects * 4 + 16))
+                bcmem = maxblocksize * (mainindex->narenas + mainindex->nsects * 4 + 16);
+        if(0) fprint(2, "initialize %d bytes of disk block cache\n", bcmem);
+        initdcache(bcmem);
+
+        clumpstats(mainindex);
+        
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/srv/config.c b/src/cmd/venti/srv/config.c
t@@ -0,0 +1,245 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+Index                        *mainindex;
+int                        paranoid = 1;                /* should verify hashes on disk read */
+
+static ArenaPart        *configarenas(char *file);
+static ISect                *configisect(char *file);
+static Bloom                *configbloom(char *file);
+
+int
+initventi(char *file, Config *conf)
+{
+        statsinit();
+
+        if(file == nil){
+                seterr(EOk, "no configuration file");
+                return -1;
+        }
+        if(runconfig(file, conf) < 0){
+                seterr(EOk, "can't initialize venti: %r");
+                return -1;
+        }
+        mainindex = initindex(conf->index, conf->sects, conf->nsects);
+        if(mainindex == nil)
+                return -1;
+        mainindex->bloom = conf->bloom;
+        return 0;
+}
+
+static int
+numok(char *s)
+{
+        char *p;
+
+        strtoull(s, &p, 0);
+        if(p == s)
+                return -1;
+        if(*p == 0)
+                return 0;
+        if(p[1] == 0 && strchr("MmGgKk", *p))
+                return 0;
+        return 0;
+}
+
+/*
+ * configs        :
+ *                | configs config
+ * config        : "isect" filename
+ *                | "arenas" filename
+ *                | "index" name
+ *                | "bcmem" num
+ *                | "mem" num
+ *                | "icmem" num
+ *                | "queuewrites"
+ *                | "httpaddr" address
+ *                | "addr" address
+ *
+ * '#' and \n delimit comments
+ */
+enum
+{
+        MaxArgs        = 2
+};
+int
+runconfig(char *file, Config *config)
+{
+        ArenaPart **av;
+        ISect **sv;
+        IFile f;
+        char *s, *line, *flds[MaxArgs + 1];
+        int i, ok;
+
+        if(readifile(&f, file) < 0)
+                return -1;
+        memset(config, 0, sizeof *config);
+        config->mem = 0xFFFFFFFFUL;
+        ok = -1;
+        line = nil;
+        for(;;){
+                s = ifileline(&f);
+                if(s == nil){
+                        ok = 0;
+                        break;
+                }
+                line = estrdup(s);
+                i = getfields(s, flds, MaxArgs + 1, 1, " \t\r");
+                if(i == 2 && strcmp(flds[0], "isect") == 0){
+                        sv = MKN(ISect*, config->nsects + 1);
+                        for(i = 0; i < config->nsects; i++)
+                                sv[i] = config->sects[i];
+                        free(config->sects);
+                        config->sects = sv;
+                        config->sects[config->nsects] = configisect(flds[1]);
+                        if(config->sects[config->nsects] == nil)
+                                break;
+                        config->nsects++;
+                }else if(i == 2 && strcmp(flds[0], "arenas") == 0){
+                        av = MKN(ArenaPart*, config->naparts + 1);
+                        for(i = 0; i < config->naparts; i++)
+                                av[i] = config->aparts[i];
+                        free(config->aparts);
+                        config->aparts = av;
+                        config->aparts[config->naparts] = configarenas(flds[1]);
+                        if(config->aparts[config->naparts] == nil)
+                                break;
+                        config->naparts++;
+                }else if(i == 2 && strcmp(flds[0], "bloom") == 0){
+                        if(config->bloom){
+                                seterr(EAdmin, "duplicate bloom lines in configuration file %s", file);
+                                break;
+                        }
+                        if((config->bloom = configbloom(flds[1])) == nil)
+                                break;
+                }else if(i == 2 && strcmp(flds[0], "index") == 0){
+                        if(nameok(flds[1]) < 0){
+                                seterr(EAdmin, "illegal index name %s in config file %s", flds[1], file);
+                                break;
+                        }
+                        if(config->index != nil){
+                                seterr(EAdmin, "duplicate indices in config file %s", file);
+                                break;
+                        }
+                        config->index = estrdup(flds[1]);
+                }else if(i == 2 && strcmp(flds[0], "bcmem") == 0){
+                        if(numok(flds[1]) < 0){
+                                seterr(EAdmin, "illegal size %s in config file %s",
+                                        flds[1], file);
+                                break;
+                        }
+                        if(config->bcmem != 0){
+                                seterr(EAdmin, "duplicate bcmem lines in config file %s", file);
+                                break;
+                        }
+                        config->bcmem = unittoull(flds[1]);
+                }else if(i == 2 && strcmp(flds[0], "mem") == 0){
+                        if(numok(flds[1]) < 0){
+                                seterr(EAdmin, "illegal size %s in config file %s",
+                                        flds[1], file);
+                                break;
+                        }
+                        if(config->mem != 0xFFFFFFFFUL){
+                                seterr(EAdmin, "duplicate mem lines in config file %s", file);
+                                break;
+                        }
+                        config->mem = unittoull(flds[1]);
+                }else if(i == 2 && strcmp(flds[0], "icmem") == 0){
+                        if(numok(flds[1]) < 0){
+                                seterr(EAdmin, "illegal size %s in config file %s",
+                                        flds[1], file);
+                                break;
+                        }
+                        if(config->icmem != 0){
+                                seterr(EAdmin, "duplicate icmem lines in config file %s", file);
+                                break;
+                        }
+                        config->icmem = unittoull(flds[1]);
+                }else if(i == 1 && strcmp(flds[0], "queuewrites") == 0){
+                        config->queuewrites = 1;
+                }else if(i == 2 && strcmp(flds[0], "httpaddr") == 0){
+                        if(config->haddr){
+                                seterr(EAdmin, "duplicate httpaddr lines in configuration file %s", file);
+                                break;
+                        }
+                        config->haddr = estrdup(flds[1]);
+                }else if(i == 2 && strcmp(flds[0], "webroot") == 0){
+                        if(config->webroot){
+                                seterr(EAdmin, "duplicate webroot lines in configuration file %s", file);
+                                break;
+                        }
+                        config->webroot = estrdup(flds[1]);
+                }else if(i == 2 && strcmp(flds[0], "addr") == 0){
+                        if(config->vaddr){
+                                seterr(EAdmin, "duplicate addr lines in configuration file %s", file);
+                                break;
+                        }
+                        config->vaddr = estrdup(flds[1]);
+                }else{
+                        seterr(EAdmin, "illegal line '%s' in configuration file %s", line, file);
+                        break;
+                }
+                free(line);
+                line = nil;
+        }
+        free(line);
+        freeifile(&f);
+        if(ok < 0){
+                free(config->sects);
+                config->sects = nil;
+                free(config->aparts);
+                config->aparts = nil;
+        }
+        return ok;
+}
+
+static ISect*
+configisect(char *file)
+{
+        Part *part;
+        ISect *is;
+        
+        if(0) fprint(2, "configure index section in %s\n", file);
+
+        part = initpart(file, ORDWR|ODIRECT);
+        if(part == nil)
+                return nil;
+        is = initisect(part);
+        if(is == nil)
+                werrstr("%s: %r", file);
+        return is;
+}
+
+static ArenaPart*
+configarenas(char *file)
+{
+        ArenaPart *ap;
+        Part *part;
+
+        if(0) fprint(2, "configure arenas in %s\n", file);
+        part = initpart(file, ORDWR|ODIRECT);
+        if(part == nil)
+                return nil;
+        ap = initarenapart(part);
+        if(ap == nil)
+                werrstr("%s: %r", file);
+        return ap;
+}
+
+static Bloom*
+configbloom(char *file)
+{
+        Bloom *b;
+        Part *part;
+
+        if(0) fprint(2, "configure bloom in %s\n", file);
+        part = initpart(file, ORDWR|ODIRECT);
+        if(part == nil)
+                return nil;
+        b = readbloom(part);
+        if(b == nil)
+                werrstr("%s: %r", file);
+        return b;
+}
+
diff --git a/src/cmd/venti/srv/conv.c b/src/cmd/venti/srv/conv.c
t@@ -0,0 +1,632 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+/*
+ * disk structure conversion routines
+ */
+#define        U8GET(p)        ((p)[0])
+#define        U16GET(p)        (((p)[0]<<8)|(p)[1])
+#define        U32GET(p)        ((u32int)(((p)[0]<<24)|((p)[1]<<16)|((p)[2]<<8)|(p)[3]))
+#define        U64GET(p)        (((u64int)U32GET(p)<<32)|(u64int)U32GET((p)+4))
+
+#define        U8PUT(p,v)        (p)[0]=(v)&0xFF
+#define        U16PUT(p,v)        (p)[0]=((v)>>8)&0xFF;(p)[1]=(v)&0xFF
+#define        U32PUT(p,v)        (p)[0]=((v)>>24)&0xFF;(p)[1]=((v)>>16)&0xFF;(p)[2]=((v)>>8)&0xFF;(p)[3]=(v)&0xFF
+#define        U64PUT(p,v,t32)        t32=(v)>>32;U32PUT(p,t32);t32=(v);U32PUT((p)+4,t32)
+
+static struct {
+        u32int m;
+        char *s;
+} magics[] = {
+        ArenaPartMagic, "ArenaPartMagic",
+        ArenaHeadMagic, "ArenaHeadMagic",
+        ArenaMagic, "ArenaMagic",
+        ISectMagic, "ISectMagic",
+        BloomMagic, "BloomMagic",
+};
+
+static char*
+fmtmagic(char *s, u32int m)
+{
+        int i;
+
+        for(i=0; iversion = U32GET(p);
+        p += U32Size;
+        ap->blocksize = U32GET(p);
+        p += U32Size;
+        ap->arenabase = U32GET(p);
+        p += U32Size;
+
+        if(buf + ArenaPartSize != p)
+                sysfatal("unpackarenapart unpacked wrong amount");
+
+        return 0;
+}
+
+int
+packarenapart(ArenaPart *ap, u8int *buf)
+{
+        u8int *p;
+
+        p = buf;
+
+        U32PUT(p, ArenaPartMagic);
+        p += U32Size;
+        U32PUT(p, ap->version);
+        p += U32Size;
+        U32PUT(p, ap->blocksize);
+        p += U32Size;
+        U32PUT(p, ap->arenabase);
+        p += U32Size;
+
+        if(buf + ArenaPartSize != p)
+                sysfatal("packarenapart packed wrong amount");
+
+        return 0;
+}
+
+int
+unpackarena(Arena *arena, u8int *buf)
+{
+        int sz;
+        u8int *p;
+        u32int m;
+        char fbuf[20];
+
+        p = buf;
+
+        m = U32GET(p);
+        if(m != ArenaMagic){
+                seterr(ECorrupt, "arena has wrong magic number: %s expected ArenaMagic (%lux)", fmtmagic(fbuf, m), ArenaMagic);
+                return -1;
+        }
+        p += U32Size;
+        arena->version = U32GET(p);
+        p += U32Size;
+        namecp(arena->name, (char*)p);
+        p += ANameSize;
+        arena->diskstats.clumps = U32GET(p);
+        p += U32Size;
+        arena->diskstats.cclumps = U32GET(p);
+        p += U32Size;
+        arena->ctime = U32GET(p);
+        p += U32Size;
+        arena->wtime = U32GET(p);
+        p += U32Size;
+        if(arena->version == ArenaVersion5){
+                arena->clumpmagic = U32GET(p);
+                p += U32Size;
+        }
+        arena->diskstats.used = U64GET(p);
+        p += U64Size;
+        arena->diskstats.uncsize = U64GET(p);
+        p += U64Size;
+        arena->diskstats.sealed = U8GET(p);
+        p += U8Size;
+
+        arena->memstats = arena->diskstats;
+
+        switch(arena->version){
+        case ArenaVersion4:
+                sz = ArenaSize4;
+                arena->clumpmagic = _ClumpMagic;
+                break;
+        case ArenaVersion5:
+                sz = ArenaSize5;
+                break;
+        default:
+                seterr(ECorrupt, "arena has bad version number %d", arena->version);
+                return -1;
+        }
+        if(buf + sz != p)
+                sysfatal("unpackarena unpacked wrong amount");
+
+        return 0;
+}
+
+int
+packarena(Arena *arena, u8int *buf)
+{
+        int sz;
+        u8int *p;
+        u32int t32;
+
+        switch(arena->version){
+        case ArenaVersion4:
+                sz = ArenaSize4;
+                if(arena->clumpmagic != _ClumpMagic)
+                        fprint(2, "warning: writing old arena tail loses clump magic 0x%lux != 0x%lux\n",
+                                (ulong)arena->clumpmagic, (ulong)_ClumpMagic);
+                break;
+        case ArenaVersion5:
+                sz = ArenaSize5;
+                break;
+        default:
+                sysfatal("packarena unknown version %d", arena->version);
+                return -1;
+        }
+
+        p = buf;
+
+        U32PUT(p, ArenaMagic);
+        p += U32Size;
+        U32PUT(p, arena->version);
+        p += U32Size;
+        namecp((char*)p, arena->name);
+        p += ANameSize;
+        U32PUT(p, arena->diskstats.clumps);
+        p += U32Size;
+        U32PUT(p, arena->diskstats.cclumps);
+        p += U32Size;
+        U32PUT(p, arena->ctime);
+        p += U32Size;
+        U32PUT(p, arena->wtime);
+        p += U32Size;
+        if(arena->version == ArenaVersion5){
+                U32PUT(p, arena->clumpmagic);
+                p += U32Size;
+        }
+        U64PUT(p, arena->diskstats.used, t32);
+        p += U64Size;
+        U64PUT(p, arena->diskstats.uncsize, t32);
+        p += U64Size;
+        U8PUT(p, arena->diskstats.sealed);
+        p += U8Size;
+
+        if(buf + sz != p)
+                sysfatal("packarena packed wrong amount");
+
+        return 0;
+}
+
+int
+unpackarenahead(ArenaHead *head, u8int *buf)
+{
+        u8int *p;
+        u32int m;
+        int sz;
+
+        p = buf;
+
+        m = U32GET(p);
+        /* XXX check magic! */
+
+        p += U32Size;
+        head->version = U32GET(p);
+        p += U32Size;
+        namecp(head->name, (char*)p);
+        p += ANameSize;
+        head->blocksize = U32GET(p);
+        p += U32Size;
+        head->size = U64GET(p);
+        p += U64Size;
+        if(head->version == ArenaVersion5){
+                head->clumpmagic = U32GET(p);
+                p += U32Size;
+        }
+
+        switch(head->version){
+        case ArenaVersion4:
+                sz = ArenaHeadSize4;
+                head->clumpmagic = _ClumpMagic;
+                break;
+        case ArenaVersion5:
+                sz = ArenaHeadSize5;
+                break;
+        default:
+                seterr(ECorrupt, "arena head has unexpected version %d", head->version);
+                return -1;
+        }
+
+        if(buf + sz != p)
+                sysfatal("unpackarenahead unpacked wrong amount");
+
+        return 0;
+}
+
+int
+packarenahead(ArenaHead *head, u8int *buf)
+{
+        u8int *p;
+        int sz;
+        u32int t32;
+
+        switch(head->version){
+        case ArenaVersion4:
+                sz = ArenaHeadSize4;
+                if(head->clumpmagic != _ClumpMagic)
+                        fprint(2, "warning: writing old arena header loses clump magic 0x%lux != 0x%lux\n",
+                                (ulong)head->clumpmagic, (ulong)_ClumpMagic);
+                break;
+        case ArenaVersion5:
+                sz = ArenaHeadSize5;
+                break;
+        default:
+                sysfatal("packarenahead unknown version %d", head->version);
+                return -1;
+        }
+
+        p = buf;
+
+        U32PUT(p, ArenaHeadMagic);
+        p += U32Size;
+        U32PUT(p, head->version);
+        p += U32Size;
+        namecp((char*)p, head->name);
+        p += ANameSize;
+        U32PUT(p, head->blocksize);
+        p += U32Size;
+        U64PUT(p, head->size, t32);
+        p += U64Size;
+        if(head->version == ArenaVersion5){
+                U32PUT(p, head->clumpmagic);
+                p += U32Size;
+        }
+        if(buf + sz != p)
+                sysfatal("packarenahead packed wrong amount");
+
+        return 0;
+}
+
+static int
+checkclump(Clump *w)
+{
+        if(w->encoding == ClumpENone){
+                if(w->info.size != w->info.uncsize){
+                        seterr(ECorrupt, "uncompressed wad size mismatch");
+                        return -1;
+                }
+        }else if(w->encoding == ClumpECompress){
+                if(w->info.size >= w->info.uncsize){
+                        seterr(ECorrupt, "compressed lump has inconsistent block sizes %d %d", w->info.size, w->info.uncsize);
+                        return -1;
+                }
+        }else{
+                seterr(ECorrupt, "clump has illegal encoding");
+                return -1;
+        }
+
+        return 0;
+}
+
+int
+unpackclump(Clump *c, u8int *buf, u32int cmagic)
+{
+        u8int *p;
+        u32int magic;
+
+        p = buf;
+        magic = U32GET(p);
+        if(magic != cmagic){
+                seterr(ECorrupt, "clump has bad magic number=%#8.8ux != %#8.8ux", magic, cmagic);
+                return -1;
+        }
+        p += U32Size;
+
+        c->info.type = vtfromdisktype(U8GET(p));
+        p += U8Size;
+        c->info.size = U16GET(p);
+        p += U16Size;
+        c->info.uncsize = U16GET(p);
+        p += U16Size;
+        scorecp(c->info.score, p);
+        p += VtScoreSize;
+
+        c->encoding = U8GET(p);
+        p += U8Size;
+        c->creator = U32GET(p);
+        p += U32Size;
+        c->time = U32GET(p);
+        p += U32Size;
+
+        if(buf + ClumpSize != p)
+                sysfatal("unpackclump unpacked wrong amount");
+
+        return checkclump(c);
+}
+
+int
+packclump(Clump *c, u8int *buf, u32int magic)
+{
+        u8int *p;
+
+        p = buf;
+        U32PUT(p, magic);
+        p += U32Size;
+
+        U8PUT(p, vttodisktype(c->info.type));
+        p += U8Size;
+        U16PUT(p, c->info.size);
+        p += U16Size;
+        U16PUT(p, c->info.uncsize);
+        p += U16Size;
+        scorecp(p, c->info.score);
+        p += VtScoreSize;
+
+        U8PUT(p, c->encoding);
+        p += U8Size;
+        U32PUT(p, c->creator);
+        p += U32Size;
+        U32PUT(p, c->time);
+        p += U32Size;
+
+        if(buf + ClumpSize != p)
+                sysfatal("packclump packed wrong amount");
+
+        return checkclump(c);
+}
+
+void
+unpackclumpinfo(ClumpInfo *ci, u8int *buf)
+{
+        u8int *p;
+
+        p = buf;
+        ci->type = vtfromdisktype(U8GET(p));
+        p += U8Size;
+        ci->size = U16GET(p);
+        p += U16Size;
+        ci->uncsize = U16GET(p);
+        p += U16Size;
+        scorecp(ci->score, p);
+        p += VtScoreSize;
+
+        if(buf + ClumpInfoSize != p)
+                sysfatal("unpackclumpinfo unpacked wrong amount");
+}
+
+void
+packclumpinfo(ClumpInfo *ci, u8int *buf)
+{
+        u8int *p;
+
+        p = buf;
+        U8PUT(p, vttodisktype(ci->type));
+        p += U8Size;
+        U16PUT(p, ci->size);
+        p += U16Size;
+        U16PUT(p, ci->uncsize);
+        p += U16Size;
+        scorecp(p, ci->score);
+        p += VtScoreSize;
+
+        if(buf + ClumpInfoSize != p)
+                sysfatal("packclumpinfo packed wrong amount");
+}
+
+int
+unpackisect(ISect *is, u8int *buf)
+{
+        u8int *p;
+        u32int m;
+        char fbuf[20];
+
+        p = buf;
+
+
+        m = U32GET(p);
+        if(m != ISectMagic){
+                seterr(ECorrupt, "index section has wrong magic number: %s expected ISectMagic (%lux)",
+                        fmtmagic(fbuf, m), ISectMagic);
+                return -1;
+        }
+        p += U32Size;
+        is->version = U32GET(p);
+        p += U32Size;
+        namecp(is->name, (char*)p);
+        p += ANameSize;
+        namecp(is->index, (char*)p);
+        p += ANameSize;
+        is->blocksize = U32GET(p);
+        p += U32Size;
+        is->blockbase = U32GET(p);
+        p += U32Size;
+        is->blocks = U32GET(p);
+        p += U32Size;
+        is->start = U32GET(p);
+        p += U32Size;
+        is->stop = U32GET(p);
+        p += U32Size;
+        if(buf + ISectSize1 != p)
+                sysfatal("unpackisect unpacked wrong amount");
+        is->bucketmagic = 0;
+        if(is->version == ISectVersion2){
+                is->bucketmagic = U32GET(p);
+                p += U32Size;
+                if(buf + ISectSize2 != p)
+                        sysfatal("unpackisect unpacked wrong amount");
+        }
+
+        return 0;
+}
+
+int
+packisect(ISect *is, u8int *buf)
+{
+        u8int *p;
+
+        p = buf;
+
+        U32PUT(p, ISectMagic);
+        p += U32Size;
+        U32PUT(p, is->version);
+        p += U32Size;
+        namecp((char*)p, is->name);
+        p += ANameSize;
+        namecp((char*)p, is->index);
+        p += ANameSize;
+        U32PUT(p, is->blocksize);
+        p += U32Size;
+        U32PUT(p, is->blockbase);
+        p += U32Size;
+        U32PUT(p, is->blocks);
+        p += U32Size;
+        U32PUT(p, is->start);
+        p += U32Size;
+        U32PUT(p, is->stop);
+        p += U32Size;
+        if(buf + ISectSize1 != p)
+                sysfatal("packisect packed wrong amount");
+        if(is->version == ISectVersion2){
+                U32PUT(p, is->bucketmagic);
+                p += U32Size;
+                if(buf + ISectSize2 != p)
+                        sysfatal("packisect packed wrong amount");
+        }
+
+        return 0;
+}
+
+void
+unpackientry(IEntry *ie, u8int *buf)
+{
+        u8int *p;
+
+        p = buf;
+
+        scorecp(ie->score, p);
+        p += VtScoreSize;
+        ie->wtime = U32GET(p);
+        p += U32Size;
+        ie->train = U16GET(p);
+        p += U16Size;
+        ie->ia.addr = U64GET(p);
+if(ie->ia.addr>>56) print("%.8H => %llux\n", p, ie->ia.addr);
+        p += U64Size;
+        ie->ia.size = U16GET(p);
+        p += U16Size;
+        if(p - buf != IEntryTypeOff)
+                sysfatal("unpackientry bad IEntryTypeOff amount");
+        ie->ia.type = vtfromdisktype(U8GET(p));
+        p += U8Size;
+        ie->ia.blocks = U8GET(p);
+        p += U8Size;
+
+        if(p - buf != IEntrySize)
+                sysfatal("unpackientry unpacked wrong amount");
+}
+
+void
+packientry(IEntry *ie, u8int *buf)
+{
+        u32int t32;
+        u8int *p;
+
+        p = buf;
+
+        scorecp(p, ie->score);
+        p += VtScoreSize;
+        U32PUT(p, ie->wtime);
+        p += U32Size;
+        U16PUT(p, ie->train);
+        p += U16Size;
+        U64PUT(p, ie->ia.addr, t32);
+        p += U64Size;
+        U16PUT(p, ie->ia.size);
+        p += U16Size;
+        U8PUT(p, vttodisktype(ie->ia.type));
+        p += U8Size;
+        U8PUT(p, ie->ia.blocks);
+        p += U8Size;
+
+        if(p - buf != IEntrySize)
+                sysfatal("packientry packed wrong amount");
+}
+
+void
+unpackibucket(IBucket *b, u8int *buf, u32int magic)
+{
+        b->n = U16GET(buf);
+        b->data = buf + IBucketSize;
+        if(magic && magic != U32GET(buf+U16Size))
+                b->n = 0;
+}                
+
+void
+packibucket(IBucket *b, u8int *buf, u32int magic)
+{
+        U16PUT(buf, b->n);
+        U32PUT(buf+U16Size, magic);
+}
+
+void
+packbloomhead(Bloom *b, u8int *buf)
+{
+        u8int *p;
+
+        p = buf;
+        U32PUT(p, BloomMagic);
+        U32PUT(p+4, BloomVersion);
+        U32PUT(p+8, b->nhash);
+        U32PUT(p+12, b->size);
+}
+
+int
+unpackbloomhead(Bloom *b, u8int *buf)
+{
+        u8int *p;
+        u32int m;
+        char fbuf[20];
+
+        p = buf;
+
+        m = U32GET(p);
+        if(m != BloomMagic){
+                seterr(ECorrupt, "bloom filter has wrong magic number: %s expected BloomMagic (%lux)", fmtmagic(fbuf, m), (ulong)BloomMagic);
+                return -1;
+        }
+        p += U32Size;
+        
+        m = U32GET(p);
+        if(m != BloomVersion){
+                seterr(ECorrupt, "bloom filter has wrong version %ud expected %ud", (uint)m, (uint)BloomVersion);
+                return -1;
+        }
+        p += U32Size;
+
+        b->nhash = U32GET(p);
+        p += U32Size;
+
+        b->size = U32GET(p);
+        p += U32Size;
+
+        if(buf + BloomHeadSize != p)
+                sysfatal("unpackarena unpacked wrong amount");
+
+        return 0;
+}
diff --git a/src/cmd/venti/srv/dat.h b/src/cmd/venti/srv/dat.h
t@@ -0,0 +1,718 @@
+typedef struct Config                Config;
+typedef struct AMap                AMap;
+typedef struct AMapN                AMapN;
+typedef struct Arena                Arena;
+typedef struct AState        AState;
+typedef struct ArenaHead        ArenaHead;
+typedef struct ArenaPart        ArenaPart;
+typedef struct ArenaTail        ArenaTail;
+typedef struct ATailStats        ATailStats;
+typedef struct CIBlock                CIBlock;
+typedef struct Clump                Clump;
+typedef struct ClumpInfo        ClumpInfo;
+typedef struct Graph Graph;
+typedef struct IAddr                IAddr;
+typedef struct IBucket                IBucket;
+typedef struct IEStream                IEStream;
+typedef struct IEntry                IEntry;
+typedef struct IFile                IFile;
+typedef struct ISect                ISect;
+typedef struct Index                Index;
+typedef struct Lump                Lump;
+typedef struct DBlock                DBlock;
+typedef struct Part                Part;
+typedef struct Statbin Statbin;
+typedef struct Statdesc        Statdesc;
+typedef struct Stats                Stats;
+typedef struct ZBlock                ZBlock;
+typedef struct Round        Round;
+typedef struct Bloom        Bloom;
+
+#define TWID32        ((u32int)~(u32int)0)
+#define TWID64        ((u64int)~(u64int)0)
+#define        TWID8        ((u8int)~(u8int)0)
+
+enum
+{
+        ABlockLog                = 9,                /* log2(512), the quantum for reading arenas */
+        ANameSize                = 64,
+        MaxDiskBlock                = 64*1024,        /* max. allowed size for a disk block */
+        MaxIoSize                = 64*1024,        /* max. allowed size for a disk io operation */
+        PartBlank                = 256*1024,        /* untouched section at beginning of partition */
+        HeadSize                = 512,                /* size of a header after PartBlank */
+        MinArenaSize                = 1*1024*1024,        /* smallest reasonable arena size */
+        IndexBase                = 1024*1024,        /* initial address to use in an index */
+        MaxIo                        = 64*1024,        /* max size of a single read or write operation */
+        ICacheBits                = 16,                /* default bits for indexing icache */
+        ICacheDepth                = 4,                /* default depth of an icache hash chain */
+        MaxAMap                        = 2*1024,        /* max. allowed arenas in an address mapping; must be < 32*1024 */
+
+        /*
+         * return codes from syncarena
+         */
+        SyncDataErr        = 1 << 0,                /* problem reading the clump data */
+        SyncCIErr        = 1 << 1,                /* found erroneous clump directory entries */
+        SyncCIZero        = 1 << 2,                /* found unwritten clump directory entries */
+        SyncFixErr        = 1 << 3,                /* error writing fixed data */
+        SyncHeader        = 1 << 4,                /* altered header fields */
+
+        /*
+         * error severity
+         */
+        EOk                        = 0,                /* error expected in normal operation */
+        EStrange,                                /* strange error that should be logged */
+        ECorrupt,                                /* corrupted data found in arenas */
+        EICorrupt,                                /* corrupted data found in index */
+        EAdmin,                                        /* should be brought to administrators' attention */
+        ECrash,                                        /* really bad internal error */
+        EBug,                                        /* a limitation which should be fixed */
+        EInconsist,                                /* inconsistencies between index and arena */
+        EMax,
+
+        /*
+         * internal disk formats for the venti archival storage system
+         */
+        /*
+         * magic numbers on disk
+         */
+        _ClumpMagic                = 0xd15cb10c,        /* clump header, deprecated */
+        ClumpFreeMagic                = 0,                /* free clump; terminates active clump log */
+
+        ArenaPartMagic                = 0xa9e4a5e7,        /* arena partition header */
+        ArenaMagic                = 0xf2a14ead,        /* arena trailer */
+        ArenaHeadMagic                = 0xd15c4ead,        /* arena header */
+        
+        BloomMagic                = 0xb1004ead,        /* bloom filter header */
+        BloomMaxHash        = 32,
+
+        ISectMagic                = 0xd15c5ec7,        /* index header */
+
+        ArenaPartVersion        = 3,
+        ArenaVersion4                = 4,
+        ArenaVersion5                = 5,
+        BloomVersion                = 1,
+        IndexVersion                = 1,
+        ISectVersion1                = 1,
+        ISectVersion2                = 2,
+
+        /*
+         * encodings of clumps on disk
+         */
+        ClumpEErr                = 0,                /* can't happen */
+        ClumpENone,                                /* plain */
+        ClumpECompress,                                /* compressed */
+        ClumpEMax,
+
+        /*
+         * sizes in bytes on disk
+         */
+        U8Size                        = 1,
+        U16Size                        = 2,
+        U32Size                        = 4,
+        U64Size                        = 8,
+
+        ArenaPartSize                = 4 * U32Size,
+        ArenaSize4                = 2 * U64Size + 6 * U32Size + ANameSize + U8Size,
+        ArenaSize5                        = ArenaSize4 + U32Size,
+        ArenaHeadSize4                = U64Size + 3 * U32Size + ANameSize,
+        ArenaHeadSize5                = ArenaHeadSize4 + U32Size,
+        BloomHeadSize        = 4 * U32Size,
+        ISectSize1                = 7 * U32Size + 2 * ANameSize,
+        ISectSize2                = ISectSize1 + U32Size,
+        ClumpInfoSize                = U8Size + 2 * U16Size + VtScoreSize,
+        ClumpSize                = ClumpInfoSize + U8Size + 3 * U32Size,
+        MaxBloomSize                = 1<<(32-3),        /* 2^32 bits */
+        MaxBloomHash        = 32,                /* bits per score */
+        /*
+         * BUG - The various block copies that manipulate entry buckets
+         * would be faster if we bumped IBucketSize up to 8 and IEntrySize up to 40,
+         * so that everything is word-aligned.  Buildindex is actually cpu-bound
+         * by the (byte at a time) copying in qsort.
+         */
+        IBucketSize                = U32Size + U16Size,
+        IEntrySize                = U64Size + U32Size + 2*U16Size + 2*U8Size + VtScoreSize,
+        IEntryTypeOff                = VtScoreSize + U64Size + U32Size + 2 * U16Size,
+
+        MaxClumpBlocks                =  (VtMaxLumpSize + ClumpSize + (1 << ABlockLog) - 1) >> ABlockLog,
+
+        /*
+         * dirty flags - order controls disk write order
+         */
+        DirtyArena                = 1,
+        DirtyArenaCib,
+        DirtyArenaTrailer,
+        DirtyMax,
+
+        VentiZZZZZZZZ
+};
+
+extern char TraceDisk[];
+extern char TraceLump[];
+extern char TraceBlock[];
+extern char TraceProc[];
+extern char TraceWork[];
+extern char TraceQuiet[];
+extern char TraceRpc[];
+
+/*
+ * results of parsing and initializing a config file
+ */
+struct Config
+{
+        char                *index;                        /* name of the index to initialize */
+        int                naparts;                /* arena partitions initialized */
+        ArenaPart        **aparts;
+        int                nsects;                        /* index sections initialized */
+        ISect                **sects;
+        Bloom        *bloom;                /* bloom filter */
+        u32int        bcmem;
+        u32int        mem;
+        u32int        icmem;
+        int                queuewrites;
+        char*        haddr;
+        char*        vaddr;
+        char*        webroot;
+};
+
+/*
+ * a Part is the low level interface to files or disks.
+ * there are two main types of partitions
+ *        arena paritions, which some number of arenas, each in a sub-partition.
+ *        index partition, which only have one subpartition.
+ */
+struct Part
+{
+        int                fd;                        /* rock for accessing the disk */
+        int                mode;
+        u64int                offset;
+        u64int                size;                        /* size of the partiton */
+        u32int                blocksize;                /* block size for reads and writes */
+        u32int                fsblocksize;        /* minimum file system block size */
+        char                *name;
+        char                *filename;
+        Channel                *writechan;                /* chan[dcache.nblock](DBlock*) */
+};
+
+/*
+ * a cached block from the partition
+ * yuck -- most of this is internal structure for the cache
+ * all other routines should only use data
+ */
+struct DBlock
+{
+        u8int        *data;
+
+        Part        *part;                        /* partition in which cached */
+        u64int        addr;                        /* base address on the partition */
+        u32int        size;                        /* amount of data available, not amount allocated; should go away */
+        u32int        mode;
+        u32int        dirty;
+        u32int        dirtying;
+        DBlock        *next;                        /* doubly linked hash chains */
+        DBlock        *prev;
+        u32int        heap;                        /* index in heap table */
+        u32int        used;                        /* last reference times */
+        u32int        used2;
+        u32int        ref;                        /* reference count */
+        RWLock        lock;                        /* for access to data only */
+        Channel        *writedonechan;        
+        void*        chanbuf[1];                /* buffer for the chan! */
+};
+
+/*
+ * a cached block from the partition
+ * yuck -- most of this is internal structure for the cache
+ * all other routines should only use data
+ * double yuck -- this is mostly the same as a DBlock
+ */
+struct Lump
+{
+        Packet        *data;
+
+        Part        *part;                        /* partition in which cached */
+        u8int        score[VtScoreSize];        /* score of packet */
+        u8int        type;                        /* type of packet */
+        u32int        size;                        /* amount of data allocated to hold packet */
+        Lump        *next;                        /* doubly linked hash chains */
+        Lump        *prev;
+        u32int        heap;                        /* index in heap table */
+        u32int        used;                        /* last reference times */
+        u32int        used2;
+        u32int        ref;                        /* reference count */
+        QLock        lock;                        /* for access to data only */
+};
+
+/*
+ * mapping between names and address ranges
+ */
+struct AMap
+{
+        u64int                start;
+        u64int                stop;
+        char                name[ANameSize];
+};
+
+/*
+ * an AMap along with a length
+ */
+struct AMapN
+{
+        int                n;
+        AMap                *map;
+};
+
+/*
+ * an ArenaPart is a partition made up of Arenas
+ * it exists because most os's don't support many partitions,
+ * and we want to have many different Arenas
+ */
+struct ArenaPart
+{
+        Part                *part;
+        u64int                size;                        /* size of underlying partition, rounded down to blocks */
+        Arena                **arenas;
+        u32int                tabbase;                /* base address of arena table on disk */
+        u32int                tabsize;                /* max. bytes in arena table */
+
+        /*
+         * fields stored on disk
+         */
+        u32int                version;
+        u32int                blocksize;                /* "optimal" block size for reads and writes */
+        u32int                arenabase;                /* base address of first arena */
+
+        /*
+         * stored in the arena mapping table on disk
+         */
+        AMap                *map;
+        int                narenas;
+};
+
+/*
+ * info about one block in the clump info cache
+ */
+struct CIBlock
+{
+        u32int                block;                        /* blocks in the directory */
+        int                offset;                        /* offsets of one clump in the data */
+        DBlock                *data;
+};
+
+/*
+ * Statistics kept in the tail. 
+ */
+struct ATailStats
+{
+        u32int                clumps;                /* number of clumps */
+        u32int                cclumps;                /* number of compressed clumps */
+        u64int                used;
+        u64int                uncsize;
+        u8int                sealed;
+};
+
+/*
+ * Arena state - represents a point in the data log
+ */
+struct AState
+{
+        Arena                *arena;
+        u64int                aa;                        /* index address */
+        ATailStats                stats;
+};
+
+/*
+ * an Arena is a log of Clumps, preceeded by an ArenaHeader,
+ * and followed by a Arena, each in one disk block.
+ * struct on disk is not always up to date, but should be self-consistent.
+ * to sync after reboot, follow clumps starting at used until ClumpFreeMagic if found.
+ * 
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ * 
+ */
+struct Arena
+{
+        QLock                lock;                        /* lock for arena fields, writing to disk */
+        Part                *part;                        /* partition in which arena lives */
+        int                blocksize;                /* size of block to read or write */
+        u64int                base;                        /* base address on disk */
+        u64int                size;                        /* total space in the arena */
+        u64int                limit;                        /* storage limit for clumps */
+        u8int                score[VtScoreSize];        /* score of the entire sealed & summed arena */
+
+        int                clumpmax;                /* ClumpInfos per block */
+        AState                mem;
+        int                inqueue;
+        DigestState        sha1;
+
+        /*
+         * fields stored on disk
+         */
+        u32int                version;
+        char                name[ANameSize];        /* text label */
+        ATailStats                memstats;
+        ATailStats                diskstats;
+        u32int                ctime;                        /* first time a block was written */
+        u32int                wtime;                        /* last time a block was written */
+        u32int                clumpmagic;
+};
+
+/*
+ * redundant storage of some fields at the beginning of each arena
+ */
+struct ArenaHead
+{
+        u32int                version;
+        char                name[ANameSize];
+        u32int                blocksize;
+        u64int                size;
+        u32int                clumpmagic;
+};
+
+/*
+ * most interesting meta information for a clump.
+ * stored in each clump's header and in the Arena's directory,
+ * stored in reverse order just prior to the arena trailer
+ */
+struct ClumpInfo
+{
+        u8int                type;
+        u16int                size;                        /* size of disk data, not including header */
+        u16int                uncsize;                /* size of uncompressed data */
+        u8int                score[VtScoreSize];        /* score of the uncompressed data only */
+};
+
+/*
+ * header for an immutable clump of data
+ */
+struct Clump
+{
+        ClumpInfo        info;
+        u8int                encoding;
+        u32int                creator;                /* initial client which wrote the block */
+        u32int                time;                        /* creation at gmt seconds since 1/1/1970 */
+};
+
+/*
+ * index of all clumps according to their score
+ * this is just a wrapper to tie together the index sections
+ * 
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ *        
+ * 
+ * 
+ *        
+ *        
+ *        
+ * 
+ */
+struct Index
+{
+        u32int                div;                        /* divisor for mapping score to bucket */
+        u32int                buckets;                /* last bucket used in disk hash table */
+        u32int                blocksize;
+        u32int                tabsize;                /* max. bytes in index config */
+        u32int                bitblocks;        //XXX remove these fields
+        u32int                maxdepth;
+        u32int                bitkeylog;
+        u32int                bitkeymask;
+
+        int                mapalloc;                /* first arena to check when adding a lump */
+        Arena                **arenas;                /* arenas in the mapping */
+        ISect                **sects;                /* sections which hold the buckets */
+        Bloom                *bloom;        /* bloom filter */
+
+        /*
+         * fields stored in config file 
+         */
+        u32int                version;
+        char                name[ANameSize];        /* text label */
+        int                nsects;
+        AMap                *smap;                        /* mapping of buckets to index sections */
+        int                narenas;
+        AMap                *amap;                        /* mapping from index addesses to arenas */
+};
+
+/*
+ * one part of the bucket storage for an index.
+ * the index blocks are sequentially allocated
+ * across all of the sections.
+ */
+struct ISect
+{
+        Part                *part;
+        int                blocklog;                /* log2(blocksize) */
+        int                buckmax;                /* max. entries in a index bucket */
+        u32int                tabbase;                /* base address of index config table on disk */
+        u32int                tabsize;                /* max. bytes in index config */
+        Channel        *writechan;
+        Channel        *writedonechan;
+
+        /*
+         * fields stored on disk
+         */
+        u32int                version;
+        u32int                bucketmagic;
+        char                name[ANameSize];        /* text label */
+        char                index[ANameSize];        /* index owning the section */
+        u32int                blocksize;                /* size of hash buckets in index */
+        u32int                blockbase;                /* address of start of on disk index table */
+        u32int                blocks;                        /* total blocks on disk; some may be unused */
+        u32int                start;                        /* first bucket in this section */
+        u32int                stop;                        /* limit of buckets in this section */
+};
+
+/*
+ * externally interesting part of an IEntry
+ */
+struct IAddr
+{
+        u64int                addr;
+        u16int                size;                        /* uncompressed size */
+        u8int                type;                        /* type of block */
+        u8int                blocks;                        /* arena io quanta for Clump + data */
+};
+
+/*
+ * entries in the index
+ * kept in IBuckets in the disk index table,
+ * cached in the memory ICache.
+ */
+struct IEntry
+{
+        u8int                score[VtScoreSize];
+        IEntry                *next;                        /* next in hash chain */
+        IEntry                *nextdirty;                 /* next in dirty chain */
+        u32int                wtime;                        /* last write time */
+        u16int                train;                        /* relative train containing the most recent ref; 0 if no ref, 1 if in same car */
+        u8int                rac;                        /* read ahead count */
+        u8int                dirty;                /* is dirty */
+        IAddr                ia;
+};
+
+/*
+ * buckets in the on disk index table
+ */
+struct IBucket
+{
+        u16int                n;                        /* number of active indices */
+        u32int                buck;                /* used by buildindex/checkindex only */
+        u8int                *data;
+};
+
+/*
+ * temporary buffers used by individual threads
+ */
+struct ZBlock
+{
+        u32int                len;
+        u32int                _size;
+        u8int                *data;
+        u8int                *free;
+};
+
+/*
+ * simple input buffer for a '\0' terminated text file
+ */
+struct IFile
+{
+        char                *name;                                /* name of the file */
+        ZBlock                *b;                                /* entire contents of file */
+        u32int                pos;                                /* current position in the file */
+};
+
+struct Statdesc
+{
+        char *name;
+        ulong max;
+};
+
+/* keep in sync with stats.c:/statdesc and httpd.c:/graphname*/
+enum
+{
+        StatRpcTotal,
+        StatRpcRead,
+        StatRpcReadOk,
+        StatRpcReadFail,
+        StatRpcReadBytes,
+        StatRpcReadTime,
+        StatRpcReadCached,
+        StatRpcReadCachedTime,
+        StatRpcReadUncached,
+        StatRpcReadUncachedTime,
+        StatRpcWrite,
+        StatRpcWriteNew,
+        StatRpcWriteOld,
+        StatRpcWriteFail,
+        StatRpcWriteBytes,
+        StatRpcWriteTime,
+        StatRpcWriteNewTime,
+        StatRpcWriteOldTime,
+
+        StatLcacheHit,
+        StatLcacheMiss,
+        StatLcacheRead,
+        StatLcacheWrite,
+        StatLcacheSize,
+        StatLcacheStall,
+        StatLcacheReadTime,
+
+        StatDcacheHit,
+        StatDcacheMiss,
+        StatDcacheLookup,
+        StatDcacheRead,
+        StatDcacheWrite,
+        StatDcacheDirty,
+        StatDcacheSize,
+        StatDcacheFlush,
+        StatDcacheStall,
+        StatDcacheLookupTime,
+
+        StatDblockStall,
+        StatLumpStall,
+
+        StatIcacheHit,
+        StatIcacheMiss,
+        StatIcacheRead,
+        StatIcacheWrite,
+        StatIcacheFill,
+        StatIcachePrefetch,
+        StatIcacheDirty,
+        StatIcacheSize,
+        StatIcacheFlush,
+        StatIcacheStall,
+        StatIcacheReadTime,
+
+        StatBloomHit,
+        StatBloomMiss,
+        StatBloomFalseMiss,
+        StatBloomLookup,
+        StatBloomOnes,
+        StatBloomBits,
+        StatBloomLookupTime,
+
+        StatApartRead,
+        StatApartReadBytes,
+        StatApartWrite,
+        StatApartWriteBytes,
+
+        StatIsectRead,
+        StatIsectReadBytes,
+        StatIsectWrite,
+        StatIsectWriteBytes,
+
+        StatSumRead,
+        StatSumReadBytes,
+
+        NStat
+};
+
+extern Statdesc statdesc[NStat];
+
+/*
+ * statistics about the operation of the server
+ * mainly for performance monitoring and profiling.
+ */
+struct Stats
+{
+        ulong                now;
+        ulong                n[NStat];
+};
+
+struct Statbin
+{
+        uint nsamp;
+        uint min;
+        uint max;
+        uint avg;
+};
+
+struct Graph
+{
+        long (*fn)(Stats*, Stats*, void*);
+        void *arg;
+        long t0;
+        long t1;
+        long min;
+        long max;
+        long wid;
+        long ht;
+        int fill;
+};
+
+/*
+ * for kicking background processes that run one round after another after another
+ */
+struct Round
+{
+        QLock        lock;
+        Rendez        start;
+        Rendez        finish;
+        Rendez        delaywait;
+        int                delaytime;
+        int                delaykick;
+        char*        name;
+        int                last;
+        int                current;
+        int                next;
+        int                doanother;
+};
+
+/*
+ * Bloom filter of stored block hashes
+ */
+struct Bloom
+{
+        RWLock lk;                /* protects nhash, nbits, tab, mb */
+        QLock mod;                /* one marker at a time, protects nb */
+        int nhash;
+        ulong size;                /* bytes in tab */
+        ulong mask;                /* to produce index */
+        u8int *data;
+        Part *part;
+        Channel *writechan;
+        Channel *writedonechan;
+};
+
+extern        Index                *mainindex;
+extern        u32int                maxblocksize;                /* max. block size used by any partition */
+extern        int                paranoid;                /* should verify hashes on disk read */
+extern        int                queuewrites;                /* put all lump writes on a queue and finish later */
+extern        int                readonly;                /* only allowed to read the disk data */
+extern        Stats                stats;
+extern        u8int                zeroscore[VtScoreSize];
+extern        int                compressblocks;
+extern        int                writestodevnull;        /* dangerous - for performance debugging */
+extern        int                collectstats;
+extern        QLock        memdrawlock;
+extern        int                icachesleeptime;
+extern        int                arenasumsleeptime;
+
+#ifndef PLAN9PORT
+#pragma varargck type "V" uchar*
+#define ODIRECT 0
+#endif
diff --git a/src/cmd/venti/srv/dcache.c b/src/cmd/venti/srv/dcache.c
t@@ -0,0 +1,816 @@
+/*
+ * Disk cache.
+ * 
+ * Caches raw disk blocks.  Getdblock() gets a block, putdblock puts it back.
+ * Getdblock has a mode parameter that determines i/o and access to a block:
+ * if mode is OREAD or ORDWR, it is read from disk if not already in memory.
+ * If mode is ORDWR or OWRITE, it is locked for exclusive use before being returned.
+ * It is *not* marked dirty -- once changes have been made, they should be noted
+ * by using dirtydblock() before putdblock().  
+ *
+ * There is a global cache lock as well as a lock on each block. 
+ * Within a thread, the cache lock can be acquired while holding a block lock,
+ * but not vice versa; and a block cannot be locked if you already hold the lock
+ * on another block.
+ * 
+ * The flush proc writes out dirty blocks in batches, one batch per dirty tag.
+ * For example, the DirtyArena blocks are all written to disk before any of the
+ * DirtyArenaCib blocks.
+ *
+ * This code used to be in charge of flushing the dirty index blocks out to 
+ * disk, but updating the index turned out to benefit from extra care.
+ * Now cached index blocks are never marked dirty.  The index.c code takes
+ * care of updating them behind our back, and uses _getdblock to update any
+ * cached copies of the blocks as it changes them on disk.
+ */
+
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+typedef struct DCache        DCache;
+
+enum
+{
+        HashLog                = 9,
+        HashSize        = 1<dirty */
+        Rendez                full;
+        Round                round;
+        DBlock                *free;                        /* list of available lumps */
+        u32int                now;                        /* ticks for usage timestamps */
+        int                size;                        /* max. size of any block; allocated to each block */
+        DBlock                **heads;                /* hash table for finding address */
+        int                nheap;                        /* number of available victims */
+        DBlock                **heap;                        /* heap for locating victims */
+        int                nblocks;                /* number of blocks allocated */
+        DBlock                *blocks;                /* array of block descriptors */
+        DBlock                **write;                /* array of block pointers to be written */
+        u8int                *mem;                        /* memory for all block descriptors */
+        int                ndirty;                        /* number of dirty blocks */
+        int                maxdirty;                /* max. number of dirty blocks */
+        Channel        *ra;
+        u8int                *rabuf;
+        u32int                ramax;
+        u32int                rasize;
+        u64int                raaddr;
+        Part                *rapart;
+
+        AState        diskstate;
+        AState        state;
+};
+
+typedef struct Ra Ra;
+struct Ra
+{
+        Part *part;
+        u64int addr;
+};
+
+static DCache        dcache;
+
+static int        downheap(int i, DBlock *b);
+static int        upheap(int i, DBlock *b);
+static DBlock        *bumpdblock(void);
+static void        delheap(DBlock *db);
+static void        fixheap(int i, DBlock *b);
+static void        flushproc(void*);
+static void        writeproc(void*);
+static void raproc(void*);
+
+void
+initdcache(u32int mem)
+{
+        DBlock *b, *last;
+        u32int nblocks, blocksize;
+        int i;
+        u8int *p;
+
+        if(mem < maxblocksize * 2)
+                sysfatal("need at least %d bytes for the disk cache", maxblocksize * 2);
+        if(maxblocksize == 0)
+                sysfatal("no max. block size given for disk cache");
+        blocksize = maxblocksize;
+        nblocks = mem / blocksize;
+        dcache.full.l = &dcache.lock;
+        dcache.nblocks = nblocks;
+        dcache.maxdirty = (nblocks * 2) / 3;
+        trace(TraceProc, "initialize disk cache with %d blocks of %d bytes, maximum %d dirty blocks\n",
+                        nblocks, blocksize, dcache.maxdirty);
+        dcache.size = blocksize;
+        dcache.heads = MKNZ(DBlock*, HashSize);
+        dcache.heap = MKNZ(DBlock*, nblocks);
+        dcache.blocks = MKNZ(DBlock, nblocks);
+        dcache.write = MKNZ(DBlock*, nblocks);
+        dcache.mem = MKNZ(u8int, (nblocks+1+128) * blocksize);
+        dcache.ra = chancreate(sizeof(Ra), 0);
+
+        last = nil;
+        p = (u8int*)(((ulong)dcache.mem+blocksize-1)&~(ulong)(blocksize-1));
+        for(i = 0; i < nblocks; i++){
+                b = &dcache.blocks[i];
+                b->data = &p[i * blocksize];
+                b->heap = TWID32;
+                b->writedonechan = chancreate(sizeof(void*), 1);
+                b->next = last;
+                last = b;
+        }
+        dcache.rabuf = &p[i*blocksize];
+        dcache.ramax = 128*blocksize;
+        dcache.raaddr = 0;
+        dcache.rapart = nil;
+
+        dcache.free = last;
+        dcache.nheap = 0;
+        setstat(StatDcacheSize, nblocks);
+        initround(&dcache.round, "dcache", 120*1000);
+
+        vtproc(flushproc, nil);
+        vtproc(delaykickroundproc, &dcache.round);
+        vtproc(raproc, nil);
+}
+
+void
+setdcachestate(AState *a)
+{
+        trace(TraceBlock, "setdcachestate %s 0x%llux clumps %d", a->arena ? a->arena->name : nil, a->aa, a->stats.clumps);
+        qlock(&dcache.lock);
+        dcache.state = *a;
+        qunlock(&dcache.lock);
+}
+
+AState
+diskstate(void)
+{
+        AState a;
+
+        qlock(&dcache.lock);
+        a = dcache.diskstate;
+        qunlock(&dcache.lock);
+        return a;
+}
+
+static void
+raproc(void *v)
+{
+        Ra ra;
+        DBlock *b;
+
+        USED(v);
+        while(recv(dcache.ra, &ra) == 1){
+                if(ra.part->size <= ra.addr)
+                        continue;
+                b = _getdblock(ra.part, ra.addr, OREAD, 2);
+                putdblock(b);
+        }
+}        
+
+void
+dreadahead(Part *part, u64int addr, int miss)
+{
+        Ra ra;
+        static struct {
+                Part *part;
+                u64int addr;
+        } lastmiss;
+        static struct {
+                Part *part;
+                u64int addr;
+                int dir;
+        } lastra;
+
+return;
+        if(miss){
+                if(lastmiss.part==part && lastmiss.addr==addr-dcache.size){
+                XRa:
+                        lastra.part = part;
+                        lastra.dir = addr-lastmiss.addr;
+                        lastra.addr = addr+lastra.dir;
+                        ra.part = part;
+                        ra.addr = lastra.addr;
+                        nbsend(dcache.ra, &ra);
+                }else if(lastmiss.part==part && lastmiss.addr==addr+dcache.size){
+                        addr -= dcache.size;
+                        goto XRa;
+                }
+        }else{
+                if(lastra.part==part && lastra.addr==addr){
+                        lastra.addr += lastra.dir;
+                        ra.part = part;
+                        ra.addr = lastra.addr;
+                        nbsend(dcache.ra, &ra);
+                }
+        }
+
+        if(miss){
+                lastmiss.part = part;
+                lastmiss.addr = addr;
+        }
+
+//        fprint(2, "%s %llx %s\n", part->name, addr, miss ? "miss" : "hit");
+}
+
+int
+rareadpart(Part *part, u64int addr, u8int *buf, uint n, int load)
+{
+        uint nn;
+        static RWLock ralock;
+
+        rlock(&ralock);
+        if(dcache.rapart==part && dcache.raaddr <= addr && addr+n <= dcache.raaddr+dcache.rasize){
+                memmove(buf, dcache.rabuf+(addr-dcache.raaddr), n);
+                runlock(&ralock);
+                return 0;
+        }
+        if(load != 2 || addr >= part->size){        /* addr >= part->size: let readpart do the error */        
+                runlock(&ralock);
+                return readpart(part, addr, buf, n);
+        }
+
+        runlock(&ralock);
+        wlock(&ralock);
+fprint(2, "raread %s %llx\n", part->name, addr);
+        nn = dcache.ramax;
+        if(addr+nn > part->size)
+                nn = part->size - addr;
+        if(readpart(part, addr, dcache.rabuf, nn) < 0){
+                wunlock(&ralock);
+                return -1;
+        }
+        memmove(buf, dcache.rabuf, n);        
+        dcache.rapart = part;
+        dcache.rasize = nn;
+        dcache.raaddr = addr;
+        wunlock(&ralock);
+
+        addstat(StatApartReadBytes, nn-n);
+        return 0;
+}
+
+static u32int
+pbhash(u64int addr)
+{
+        u32int h;
+
+#define hashit(c)        ((((c) * 0x6b43a9b5) >> (32 - HashLog)) & HashMask)
+        h = (addr >> 32) ^ addr;
+        return hashit(h);
+}
+
+DBlock*
+getdblock(Part *part, u64int addr, int mode)
+{
+        DBlock *b;
+        uint ms;
+        
+        ms = msec();
+        b = _getdblock(part, addr, mode, 1);
+        if(mode == OREAD || mode == ORDWR)
+                addstat(StatDcacheRead, 1);
+        if(mode == OWRITE || mode == ORDWR)
+                addstat(StatDcacheWrite, 1);
+        ms = msec() - ms;
+        addstat2(StatDcacheLookup, 1, StatDcacheLookupTime, ms);
+        return b;
+}
+
+DBlock*
+_getdblock(Part *part, u64int addr, int mode, int load)
+{
+        DBlock *b;
+        u32int h, size;
+
+        trace(TraceBlock, "getdblock enter %s 0x%llux", part->name, addr);
+        size = part->blocksize;
+        if(size > dcache.size){
+                seterr(EAdmin, "block size %d too big for cache with size %d", size, dcache.size);
+                return nil;
+        }
+        h = pbhash(addr);
+
+        /*
+         * look for the block in the cache
+         */
+//checkdcache();
+        qlock(&dcache.lock);
+again:
+        for(b = dcache.heads[h]; b != nil; b = b->next){
+                if(b->part == part && b->addr == addr){
+                        /*
+                        qlock(&stats.lock);
+                        stats.pchit++;
+                        qunlock(&stats.lock);
+                        */
+                        if(load){
+                                addstat(StatDcacheHit, 1);
+                                if(load != 2 && mode != OWRITE)
+                                        dreadahead(part, b->addr, 0);
+                        }
+                        goto found;
+                }
+        }
+
+        /*
+         * missed: locate the block with the oldest second to last use.
+         * remove it from the heap, and fix up the heap.
+         */
+        if(!load){
+                qunlock(&dcache.lock);
+                return nil;
+        }
+
+        addstat(StatDcacheMiss, 1);
+
+        b = bumpdblock();
+        if(b == nil){
+                trace(TraceBlock, "all disk cache blocks in use");
+                addstat(StatDcacheStall, 1);
+                rsleep(&dcache.full);
+                addstat(StatDcacheStall, -1);
+                goto again;
+        }
+
+        assert(!b->dirty);
+
+        /*
+         * the new block has no last use, so assume it happens sometime in the middle
+ZZZ this is not reasonable
+         */
+        b->used = (b->used2 + dcache.now) / 2;
+
+        /*
+         * rechain the block on the correct hash chain
+         */
+        b->next = dcache.heads[h];
+        dcache.heads[h] = b;
+        if(b->next != nil)
+                b->next->prev = b;
+        b->prev = nil;
+
+        b->addr = addr;
+        b->part = part;
+        b->size = 0;
+        if(load != 2 && mode != OWRITE)
+                dreadahead(part, b->addr, 1);
+
+found:
+        b->ref++;
+        b->used2 = b->used;
+        b->used = dcache.now++;
+        if(b->heap != TWID32)
+                fixheap(b->heap, b);
+
+        qunlock(&dcache.lock);
+//checkdcache();
+
+        trace(TraceBlock, "getdblock lock");
+        addstat(StatDblockStall, 1);
+        if(mode == OREAD)
+                rlock(&b->lock);
+        else
+                wlock(&b->lock);
+        addstat(StatDblockStall, -1);
+        trace(TraceBlock, "getdblock locked");
+
+        if(b->size != size){
+                if(mode == OREAD){
+                        addstat(StatDblockStall, 1);
+                        runlock(&b->lock);
+                        wlock(&b->lock);
+                        addstat(StatDblockStall, -1);
+                }
+                if(b->size < size){
+                        if(mode == OWRITE)
+                                memset(&b->data[b->size], 0, size - b->size);
+                        else{
+                                trace(TraceBlock, "getdblock readpart %s 0x%llux", part->name, addr);
+                                if(rareadpart(part, addr + b->size, &b->data[b->size], size - b->size, load) < 0){
+                                        b->mode = ORDWR;        /* so putdblock wunlocks */
+                                        putdblock(b);
+                                        return nil;
+                                }
+                                trace(TraceBlock, "getdblock readpartdone");
+                                addstat(StatApartRead, 1);
+                                addstat(StatApartReadBytes, size-b->size);
+                        }
+                }
+                b->size = size;
+                if(mode == OREAD){
+                        addstat(StatDblockStall, 1);
+                        wunlock(&b->lock);
+                        rlock(&b->lock);
+                        addstat(StatDblockStall, -1);
+                }
+        }
+
+        b->mode = mode;
+        trace(TraceBlock, "getdblock exit");
+        return b;
+}
+
+void
+putdblock(DBlock *b)
+{
+        if(b == nil)
+                return;
+
+        trace(TraceBlock, "putdblock %s 0x%llux", b->part->name, b->addr);
+
+        if(b->mode == OREAD)
+                runlock(&b->lock);
+        else
+                wunlock(&b->lock);
+
+//checkdcache();
+        qlock(&dcache.lock);
+        if(--b->ref == 0 && !b->dirty){
+                if(b->heap == TWID32)
+                        upheap(dcache.nheap++, b);
+                rwakeupall(&dcache.full);
+        }
+        qunlock(&dcache.lock);
+//checkdcache();
+}
+
+void
+dirtydblock(DBlock *b, int dirty)
+{
+        int odirty;
+        Part *p;
+
+
+        trace(TraceBlock, "dirtydblock enter %s 0x%llux %d from 0x%lux", b->part->name, b->addr, dirty, getcallerpc(&b));
+        assert(b->ref != 0);
+        assert(b->mode==ORDWR || b->mode==OWRITE);
+
+        odirty = b->dirty;
+        if(b->dirty)
+                assert(b->dirty == dirty);
+        else
+                b->dirty = dirty;
+
+        p = b->part;
+        if(p->writechan == nil){
+                trace(TraceBlock, "dirtydblock allocwriteproc %s", p->name);
+                /* XXX hope this doesn't fail! */
+                p->writechan = chancreate(sizeof(DBlock*), dcache.nblocks);
+                vtproc(writeproc, p);
+        }
+        qlock(&dcache.lock);
+        if(!odirty){
+                dcache.ndirty++;
+                setstat(StatDcacheDirty, dcache.ndirty);
+                if(dcache.ndirty >= dcache.maxdirty)
+                        kickround(&dcache.round, 0);
+                else
+                        delaykickround(&dcache.round);
+        }
+        qunlock(&dcache.lock);
+}
+
+/*
+ * remove some block from use and update the free list and counters
+ */
+static DBlock*
+bumpdblock(void)
+{
+        DBlock *b;
+        ulong h;
+
+        trace(TraceBlock, "bumpdblock enter");
+        b = dcache.free;
+        if(b != nil){
+                dcache.free = b->next;
+                return b;
+        }
+
+        if(dcache.ndirty >= dcache.maxdirty)
+                kickdcache();
+
+        /*
+         * remove blocks until we find one that is unused
+         * referenced blocks are left in the heap even though
+         * they can't be scavenged; this is simple a speed optimization
+         */
+        for(;;){
+                if(dcache.nheap == 0){
+                        kickdcache();
+                        trace(TraceBlock, "bumpdblock gotnothing");
+                        return nil;
+                }
+                b = dcache.heap[0];
+                delheap(b);
+                if(!b->ref && !b->dirty)
+                        break;
+        }
+
+        trace(TraceBlock, "bumpdblock bumping %s 0x%llux", b->part->name, b->addr);
+
+        /*
+         * unchain the block
+         */
+        if(b->prev == nil){
+                h = pbhash(b->addr);
+                if(dcache.heads[h] != b)
+                        sysfatal("bad hash chains in disk cache");
+                dcache.heads[h] = b->next;
+        }else
+                b->prev->next = b->next;
+        if(b->next != nil)
+                b->next->prev = b->prev;
+
+        return b;
+}
+
+/*
+ * delete an arbitrary block from the heap
+ */
+static void
+delheap(DBlock *db)
+{
+        if(db->heap == TWID32)
+                return;
+        fixheap(db->heap, dcache.heap[--dcache.nheap]);
+        db->heap = TWID32;
+}
+
+/*
+ * push an element up or down to it's correct new location
+ */
+static void
+fixheap(int i, DBlock *b)
+{
+        if(upheap(i, b) == i)
+                downheap(i, b);
+}
+
+static int
+upheap(int i, DBlock *b)
+{
+        DBlock *bb;
+        u32int now;
+        int p;
+
+        now = dcache.now;
+        for(; i != 0; i = p){
+                p = (i - 1) >> 1;
+                bb = dcache.heap[p];
+                if(b->used2 - now >= bb->used2 - now)
+                        break;
+                dcache.heap[i] = bb;
+                bb->heap = i;
+        }
+
+        dcache.heap[i] = b;
+        b->heap = i;
+        return i;
+}
+
+static int
+downheap(int i, DBlock *b)
+{
+        DBlock *bb;
+        u32int now;
+        int k;
+
+        now = dcache.now;
+        for(; ; i = k){
+                k = (i << 1) + 1;
+                if(k >= dcache.nheap)
+                        break;
+                if(k + 1 < dcache.nheap && dcache.heap[k]->used2 - now > dcache.heap[k + 1]->used2 - now)
+                        k++;
+                bb = dcache.heap[k];
+                if(b->used2 - now <= bb->used2 - now)
+                        break;
+                dcache.heap[i] = bb;
+                bb->heap = i;
+        }
+
+        dcache.heap[i] = b;
+        b->heap = i;
+        return i;
+}
+
+static void
+findblock(DBlock *bb)
+{
+        DBlock *b, *last;
+        int h;
+
+        last = nil;
+        h = pbhash(bb->addr);
+        for(b = dcache.heads[h]; b != nil; b = b->next){
+                if(last != b->prev)
+                        sysfatal("bad prev link");
+                if(b == bb)
+                        return;
+                last = b;
+        }
+        sysfatal("block missing from hash table");
+}
+
+void
+checkdcache(void)
+{
+        DBlock *b;
+        u32int size, now;
+        int i, k, refed, nfree;
+
+        qlock(&dcache.lock);
+        size = dcache.size;
+        now = dcache.now;
+        for(i = 0; i < dcache.nheap; i++){
+                if(dcache.heap[i]->heap != i)
+                        sysfatal("dc: mis-heaped at %d: %d", i, dcache.heap[i]->heap);
+                if(i > 0 && dcache.heap[(i - 1) >> 1]->used2 - now > dcache.heap[i]->used2 - now)
+                        sysfatal("dc: bad heap ordering");
+                k = (i << 1) + 1;
+                if(k < dcache.nheap && dcache.heap[i]->used2 - now > dcache.heap[k]->used2 - now)
+                        sysfatal("dc: bad heap ordering");
+                k++;
+                if(k < dcache.nheap && dcache.heap[i]->used2 - now > dcache.heap[k]->used2 - now)
+                        sysfatal("dc: bad heap ordering");
+        }
+
+        refed = 0;
+        for(i = 0; i < dcache.nblocks; i++){
+                b = &dcache.blocks[i];
+                if(b->data != &dcache.mem[i * size])
+                        sysfatal("dc: mis-blocked at %d", i);
+                if(b->ref && b->heap == TWID32)
+                        refed++;
+                if(b->addr)
+                        findblock(b);
+                if(b->heap != TWID32
+                && dcache.heap[b->heap] != b)
+                        sysfatal("dc: spurious heap value");
+        }
+
+        nfree = 0;
+        for(b = dcache.free; b != nil; b = b->next){
+                if(b->addr != 0 || b->heap != TWID32)
+                        sysfatal("dc: bad free list");
+                nfree++;
+        }
+
+        if(dcache.nheap + nfree + refed != dcache.nblocks)
+                sysfatal("dc: missing blocks: %d %d %d", dcache.nheap, refed, dcache.nblocks);
+        qunlock(&dcache.lock);
+}
+
+void
+flushdcache(void)
+{
+        trace(TraceProc, "flushdcache enter");
+        kickround(&dcache.round, 1);
+        trace(TraceProc, "flushdcache exit");
+}
+
+void
+kickdcache(void)
+{
+        kickround(&dcache.round, 0);
+}
+
+static int
+parallelwrites(DBlock **b, DBlock **eb, int dirty)
+{
+        DBlock **p, **q;
+        for(p=b; pdirty == dirty; p++){
+                assert(b<=p && ppart->writechan, *p);
+        }
+        q = p;
+        for(p=b; pwritedonechan);
+        }
+
+        return p-b;
+}
+
+/*
+ * Sort first by dirty flag, then by partition, then by address in partition.
+ */
+static int
+writeblockcmp(const void *va, const void *vb)
+{
+        DBlock *a, *b;
+
+        a = *(DBlock**)va;
+        b = *(DBlock**)vb;
+
+        if(a->dirty != b->dirty)
+                return a->dirty - b->dirty;
+        if(a->part != b->part){
+                if(a->part < b->part)
+                        return -1;
+                if(a->part > b->part)
+                        return 1;
+        }
+        if(a->addr < b->addr)
+                return -1;
+        return 1;
+}
+
+static void
+flushproc(void *v)
+{
+        int i, j, n;
+        ulong t0;
+        DBlock *b, **write;
+        AState as;
+
+        USED(v);
+        threadsetname("flushproc");
+        for(;;){
+                waitforkick(&dcache.round);
+
+                trace(TraceWork, "start");
+                qlock(&dcache.lock);
+                as = dcache.state;
+                qunlock(&dcache.lock);
+
+                t0 = nsec()/1000;
+
+                trace(TraceProc, "build t=%lud", (ulong)(nsec()/1000)-t0);
+                write = dcache.write;
+                n = 0;
+                for(i=0; idirty)
+                                write[n++] = b;
+                }
+
+                qsort(write, n, sizeof(write[0]), writeblockcmp);
+
+                /* Write each stage of blocks out. */
+                trace(TraceProc, "writeblocks t=%lud", (ulong)(nsec()/1000)-t0);
+                i = 0;
+                for(j=1; jdirty);
+                        abort();
+                }
+
+/* XXX
+* the locking here is suspect.  what if a block is redirtied
+* after the write happens?  we'll still decrement dcache.ndirty here.
+*/
+                trace(TraceProc, "undirty.%d t=%lud", j, (ulong)(nsec()/1000)-t0);
+                qlock(&dcache.lock);
+                dcache.diskstate = as;
+                for(i=0; iref == 0 && b->heap == TWID32){
+                                upheap(dcache.nheap++, b);
+                                rwakeupall(&dcache.full);
+                        }
+                }
+                setstat(StatDcacheDirty, dcache.ndirty);
+                qunlock(&dcache.lock);
+                addstat(StatDcacheFlush, 1);
+                trace(TraceWork, "finish");
+        }
+}
+
+static void
+writeproc(void *v)
+{
+        DBlock *b;
+        Part *p;
+
+        p = v;
+
+        threadsetname("writeproc:%s", p->name);
+        for(;;){
+                b = recvp(p->writechan);
+                trace(TraceWork, "start");
+                assert(b->part == p);
+                trace(TraceProc, "wlock %s 0x%llux", p->name, b->addr);
+                wlock(&b->lock);
+                trace(TraceProc, "writepart %s 0x%llux", p->name, b->addr);
+                if(writepart(p, b->addr, b->data, b->size) < 0)
+                        fprint(2, "write error: %r\n"); /* XXX details! */
+                addstat(StatApartWrite, 1);
+                addstat(StatApartWriteBytes, b->size);
+                b->dirty = 0;
+                wunlock(&b->lock);
+                trace(TraceProc, "finish %s 0x%llux", p->name, b->addr);
+                trace(TraceWork, "finish");
+                sendp(b->writedonechan, b);
+        }
+}
diff --git a/src/cmd/venti/srv/dump.c b/src/cmd/venti/srv/dump.c
t@@ -0,0 +1,47 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+void
+printindex(int fd, Index *ix)
+{
+        int i;
+
+        fprint(fd, "index=%s version=%d blocksize=%d tabsize=%d\n",
+                ix->name, ix->version, ix->blocksize, ix->tabsize);
+        fprint(fd, "\tbuckets=%d div=%d\n", ix->buckets, ix->div);
+        for(i = 0; i < ix->nsects; i++)
+                fprint(fd, "\tsect=%s for buckets [%lld,%lld)\n", ix->smap[i].name, ix->smap[i].start, ix->smap[i].stop);
+        for(i = 0; i < ix->narenas; i++)
+                fprint(fd, "\tarena=%s at [%lld,%lld)\n", ix->amap[i].name, ix->amap[i].start, ix->amap[i].stop);
+}
+
+void
+printarenapart(int fd, ArenaPart *ap)
+{
+        int i;
+
+        fprint(fd, "arena partition=%s\n\tversion=%d blocksize=%d arenas=%d\n\tsetbase=%d setsize=%d\n",
+                ap->part->name, ap->version, ap->blocksize, ap->narenas, ap->tabbase, ap->tabsize);
+        for(i = 0; i < ap->narenas; i++)
+                fprint(fd, "\tarena=%s at [%lld,%lld)\n", ap->map[i].name, ap->map[i].start, ap->map[i].stop);
+}
+
+void
+printarena(int fd, Arena *arena)
+{
+        fprint(fd, "arena='%s' [%lld,%lld)\n\tversion=%d created=%d modified=%d",
+                arena->name, arena->base, arena->base + arena->size + 2 * arena->blocksize,
+                arena->version, arena->ctime, arena->wtime);
+        if(arena->memstats.sealed)
+                fprint(2, " sealed\n");
+        else
+                fprint(2, "\n");
+        if(scorecmp(zeroscore, arena->score) != 0)
+                fprint(2, "\tscore=%V\n", arena->score);
+
+        fprint(fd, "\tclumps=%,d compressed clumps=%,d data=%,lld compressed data=%,lld disk storage=%,lld\n",
+                arena->memstats.clumps, arena->memstats.cclumps, arena->memstats.uncsize,
+                arena->memstats.used - arena->memstats.clumps * ClumpSize,
+                arena->memstats.used + arena->memstats.clumps * ClumpInfoSize);
+}
diff --git a/src/cmd/venti/srv/findscore.c b/src/cmd/venti/srv/findscore.c
t@@ -0,0 +1,121 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+enum
+{
+        ClumpChunks        = 32*1024
+};
+
+static int        verbose;
+
+int
+clumpinfoeq(ClumpInfo *c, ClumpInfo *d)
+{
+        return c->type == d->type
+                && c->size == d->size
+                && c->uncsize == d->uncsize
+                && scorecmp(c->score, d->score)==0;
+}
+
+int
+findscore(Arena *arena, uchar *score)
+{
+        IEntry ie;
+        ClumpInfo *ci, *cis;
+        u64int a;
+        u32int clump;
+        int i, n, found;
+
+//ZZZ remove fprint?
+        if(arena->memstats.clumps)
+                fprint(2, "reading directory for arena=%s with %d entries\n", arena->name, arena->memstats.clumps);
+
+        cis = MKN(ClumpInfo, ClumpChunks);
+        found = 0;
+        a = 0;
+        memset(&ie, 0, sizeof(IEntry));
+        for(clump = 0; clump < arena->memstats.clumps; clump += n){
+                n = ClumpChunks;
+                if(n > arena->memstats.clumps - clump)
+                        n = arena->memstats.clumps - clump;
+                if(readclumpinfos(arena, clump, cis, n) != n){
+                        seterr(EOk, "arena directory read failed: %r");
+                        break;
+                }
+
+                for(i = 0; i < n; i++){
+                        ci = &cis[i];
+                        if(scorecmp(score, ci->score)==0){
+                                fprint(2, "found at clump=%d with type=%d size=%d csize=%d position=%lld\n",
+                                        clump + i, ci->type, ci->uncsize, ci->size, a);
+                                found++;
+                        }
+                        a += ci->size + ClumpSize;
+                }
+        }
+        free(cis);
+        return found;
+}
+
+void
+usage(void)
+{
+        fprint(2, "usage: findscore [-v] arenafile score\n");
+        threadexitsall(0);
+}
+
+void
+threadmain(int argc, char *argv[])
+{
+        ArenaPart *ap;
+        Part *part;
+        char *file;
+        u8int score[VtScoreSize];
+        int i, found;
+
+        ventifmtinstall();
+
+        ARGBEGIN{
+        case 'v':
+                verbose++;
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        readonly = 1;
+
+        if(argc != 2)
+                usage();
+
+        file = argv[0];
+        if(strscore(argv[1], score) < 0)
+                sysfatal("bad score %s\n", argv[1]);
+
+        part = initpart(file, OREAD|ODIRECT);
+        if(part == nil)
+                sysfatal("can't open partition %s: %r", file);
+
+        ap = initarenapart(part);
+        if(ap == nil)
+                sysfatal("can't initialize arena partition in %s: %r", file);
+
+        if(verbose > 1){
+                printarenapart(2, ap);
+                fprint(2, "\n");
+        }
+
+        initdcache(8 * MaxDiskBlock);
+
+        found = 0;
+        for(i = 0; i < ap->narenas; i++)
+                found += findscore(ap->arenas[i], score);
+
+        print("found %d occurrences of %V\n", found, score);
+
+        if(verbose > 1)
+                printstats();
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/srv/fmtarenas.c b/src/cmd/venti/srv/fmtarenas.c
t@@ -0,0 +1,135 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+#ifndef ODIRECT
+#define ODIRECT 0
+#endif
+
+void
+usage(void)
+{
+        fprint(2, "usage: fmtarenas [-Z] [-b blocksize] [-a arenasize] name file\n");
+        threadexitsall(0);
+}
+
+void
+threadmain(int argc, char *argv[])
+{
+        int vers;
+        ArenaPart *ap;
+        Part *part;
+        Arena *arena;
+        u64int addr, limit, asize, apsize;
+        char *file, *name, aname[ANameSize];
+        int i, n, blocksize, tabsize, zero;
+
+        ventifmtinstall();
+        statsinit();
+
+        blocksize = 8 * 1024;
+        asize = 512 * 1024 *1024;
+        tabsize = 512 * 1024;                /* BUG: should be determine from number of arenas */
+        zero = -1;
+        vers = ArenaVersion5;
+        ARGBEGIN{
+        case 'D':
+                settrace(EARGF(usage()));
+                break;
+        case 'a':
+                asize = unittoull(ARGF());
+                if(asize == TWID64)
+                        usage();
+                break;
+        case 'b':
+                blocksize = unittoull(ARGF());
+                if(blocksize == ~0)
+                        usage();
+                if(blocksize > MaxDiskBlock){
+                        fprint(2, "block size too large, max %d\n", MaxDiskBlock);
+                        threadexitsall("usage");
+                }
+                break;
+        case '4':
+                vers = ArenaVersion4;
+                break;
+        case 'Z':
+                zero = 0;
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        if(zero == -1){
+                if(vers == ArenaVersion4)
+                        zero = 1;
+                else
+                        zero = 0;
+        }
+
+        if(argc != 2)
+                usage();
+
+        name = argv[0];
+        file = argv[1];
+
+        if(nameok(name) < 0)
+                sysfatal("illegal name template %s", name);
+
+        part = initpart(file, ORDWR|ODIRECT);
+        if(part == nil)
+                sysfatal("can't open partition %s: %r", file);
+
+        if(zero)
+                zeropart(part, blocksize);
+
+        maxblocksize = blocksize;
+        initdcache(20*blocksize);
+
+        ap = newarenapart(part, blocksize, tabsize);
+        if(ap == nil)
+                sysfatal("can't initialize arena: %r");
+
+        apsize = ap->size - ap->arenabase;
+        n = apsize / asize;
+        if(apsize - (n * asize) >= MinArenaSize)
+                n++;
+
+        fprint(2, "fmtarenas %s: %,d arenas, %,lld bytes storage, %,d bytes for index map\n",
+                file, n, apsize, ap->tabsize);
+
+        ap->narenas = n;
+        ap->map = MKNZ(AMap, n);
+        ap->arenas = MKNZ(Arena*, n);
+
+        addr = ap->arenabase;
+        for(i = 0; i < n; i++){
+                limit = addr + asize;
+                if(limit >= ap->size || ap->size - limit < MinArenaSize){
+                        limit = ap->size;
+                        if(limit - addr < MinArenaSize)
+                                sysfatal("bad arena set math: runt arena at %lld,%lld %lld\n", addr, limit, ap->size);
+                }
+
+                snprint(aname, ANameSize, "%s%d", name, i);
+
+                if(0) fprint(2, "adding arena %s at [%lld,%lld)\n", aname, addr, limit);
+
+                arena = newarena(part, vers, aname, addr, limit - addr, blocksize);
+                if(!arena)
+                        fprint(2, "can't make new arena %s: %r", aname);
+                freearena(arena);
+
+                ap->map[i].start = addr;
+                ap->map[i].stop = limit;
+                namecp(ap->map[i].name, aname);
+
+                addr = limit;
+        }
+
+        if(wbarenapart(ap) < 0)
+                fprint(2, "can't write back arena partition header for %s: %r\n", file);
+
+        flushdcache();
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/srv/fmtbloom.c b/src/cmd/venti/srv/fmtbloom.c
t@@ -0,0 +1,115 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+Bloom b;
+
+void
+usage(void)
+{
+        fprint(2, "usage: fmtbloom [-s size] [-n nblocks | -N nhash] file\n");
+        threadexitsall(0);
+}
+
+void
+threadmain(int argc, char *argv[])
+{
+        Part *part;
+        char *file;
+        vlong bits, size, size2;
+        int nhash;
+        vlong nblocks;
+        
+        ventifmtinstall();
+        statsinit();
+
+        size = 0;
+        nhash = nblocks = 0;
+        ARGBEGIN{
+        case 'n':
+                if(nhash || nblocks)
+                        usage();
+                nblocks = unittoull(EARGF(usage()));
+                break;
+        case 'N':
+                if(nhash || nblocks)
+                        usage();
+                nhash = unittoull(EARGF(usage()));
+                if(nhash > BloomMaxHash){
+                        fprint(2, "maximum possible is -N %d", BloomMaxHash);
+                        usage();
+                }
+                break;
+        case 's':
+                size = unittoull(ARGF());
+                if(size == ~0)
+                        usage();
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        if(argc != 1)
+                usage();
+
+        file = argv[0];
+
+        part = initpart(file, ORDWR|ODIRECT);
+        if(part == nil)
+                sysfatal("can't open partition %s: %r", file);
+
+        if(size == 0)
+                size = part->size;
+        
+        if(size < 1024*1024)
+                sysfatal("bloom filter too small");
+
+        if(size > MaxBloomSize){
+                fprint(2, "warning: not using entire %,lld bytes; using only %,lld bytes\n",
+                        size, MaxBloomSize);
+                size = MaxBloomSize;
+        }
+        if(size&(size-1)){
+                for(size2=1; size2= nblocks*64)
+                        size2 >>= 1;
+                if(size2 != size){
+                        size = size2;
+                        fprint(2, "warning: using only %lldMB - not enough blocks to warrant more\n",
+                                size/1024/1024);
+                }
+
+                /*
+                 * optimal is to use ln 2 times as many hash functions as we have bits per blocks.  
+                 */
+                bits = (8*size)/nblocks;
+                nhash = bits*7/10;
+                if(nhash > BloomMaxHash)
+                        nhash = BloomMaxHash;
+        }
+        if(!nhash)
+                nhash = BloomMaxHash;
+        if(bloominit(&b, size, nil) < 0)
+                sysfatal("bloominit: %r");
+        b.nhash = nhash;
+        bits = nhash*10/7;
+        nblocks = (8*size)/bits;
+        fprint(2, "fmtbloom: using %lldMB, %d hashes/score, best up to %,lld blocks\n", size, nhash, nblocks);
+        b.data = vtmallocz(size);
+        b.part = part;
+        if(writebloom(&b) < 0)
+                sysfatal("writing %s: %r", file);
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/srv/fmtindex.c b/src/cmd/venti/srv/fmtindex.c
t@@ -0,0 +1,120 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+void
+usage(void)
+{
+        fprint(2, "usage: fmtindex [-a] config\n");
+        threadexitsall(0);
+}
+
+void
+threadmain(int argc, char *argv[])
+{
+        Config conf;
+        Index *ix;
+        ArenaPart *ap;
+        Arena **arenas;
+        AMap *amap;
+        u64int addr;
+        char *file;
+        u32int i, j, n, narenas;
+        int add;
+
+        ventifmtinstall();
+        statsinit();
+
+        add = 0;
+        ARGBEGIN{
+        case 'a':
+                add = 1;
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        if(argc != 1)
+                usage();
+
+        file = argv[0];
+
+        if(runconfig(file, &conf) < 0)
+                sysfatal("can't initialize config %s: %r", file);
+        if(conf.index == nil)
+                sysfatal("no index specified in %s", file);
+        if(nameok(conf.index) < 0)
+                sysfatal("illegal index name %s", conf.index);
+
+        narenas = 0;
+        for(i = 0; i < conf.naparts; i++){
+                ap = conf.aparts[i];
+                narenas += ap->narenas;
+        }
+
+        if(add){
+                ix = initindex(conf.index, conf.sects, conf.nsects);
+                if(ix == nil)
+                        sysfatal("can't initialize index %s: %r", conf.index);
+        }else{
+                ix = newindex(conf.index, conf.sects, conf.nsects);
+                if(ix == nil)
+                        sysfatal("can't create new index %s: %r", conf.index);
+
+                n = 0;
+                for(i = 0; i < ix->nsects; i++)
+                        n += ix->sects[i]->blocks;
+
+                if(0) fprint(2, "using %ud buckets of %ud; div=%d\n", ix->buckets, n, ix->div);
+        }
+        amap = MKNZ(AMap, narenas);
+        arenas = MKNZ(Arena*, narenas);
+
+        addr = IndexBase;
+        n = 0;
+        for(i = 0; i < conf.naparts; i++){
+                ap = conf.aparts[i];
+                for(j = 0; j < ap->narenas; j++){
+                        if(n >= narenas)
+                                sysfatal("too few slots in index's arena set");
+
+                        arenas[n] = ap->arenas[j];
+                        if(n < ix->narenas){
+                                if(arenas[n] != ix->arenas[n])
+                                        sysfatal("mismatched arenas %s and %s at slot %d\n",
+                                                arenas[n]->name, ix->arenas[n]->name, n);
+                                amap[n] = ix->amap[n];
+                                if(amap[n].start != addr)
+                                        sysfatal("mis-located arena %s in index %s\n", arenas[n]->name, ix->name);
+                                addr = amap[n].stop;
+                        }else{
+                                amap[n].start = addr;
+                                addr += ap->arenas[j]->size;
+                                amap[n].stop = addr;
+                                namecp(amap[n].name, ap->arenas[j]->name);
+                                if(0) fprint(2, "add arena %s at [%lld,%lld)\n",
+                                        amap[n].name, amap[n].start, amap[n].stop);
+                        }
+
+                        n++;
+                }
+        }
+        if(0){
+                fprint(2, "configured index=%s with arenas=%d and storage=%lld\n",
+                        ix->name, n, addr - IndexBase);
+                fprint(2, "\tbitblocks=%d maxdepth=%d buckets=%d\n",
+                        ix->bitblocks, ix->maxdepth, ix->buckets);
+        }
+        fprint(2, "fmtindex: %,d arenas, %,d index buckets, %,lld bytes storage\n",
+                n, ix->buckets, addr-IndexBase);
+
+        ix->amap = amap;
+        ix->arenas = arenas;
+        ix->narenas = narenas;
+
+        if(wbindex(ix) < 0)
+                fprint(2, "can't write back arena partition header for %s: %r\n", file);
+
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/srv/fmtisect.c b/src/cmd/venti/srv/fmtisect.c
t@@ -0,0 +1,83 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+void
+usage(void)
+{
+        fprint(2, "usage: fmtisect [-Z] [-b blocksize] name file\n");
+        threadexitsall(0);
+}
+
+void
+threadmain(int argc, char *argv[])
+{
+        int vers;
+        ISect *is;
+        Part *part;
+        char *file, *name;
+        int blocksize, setsize, zero;
+
+        ventifmtinstall();
+        statsinit();
+
+        blocksize = 8 * 1024;
+        setsize = 512 * 1024;
+        zero = -1;
+        vers = ISectVersion2;
+        ARGBEGIN{
+        case 'b':
+                blocksize = unittoull(ARGF());
+                if(blocksize == ~0)
+                        usage();
+                if(blocksize > MaxDiskBlock){
+                        fprint(2, "block size too large, max %d\n", MaxDiskBlock);
+                        threadexitsall("usage");
+                }
+                break;
+        case '1':
+                vers = ISectVersion1;
+                break;
+        case 'Z':
+                zero = 0;
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        if(zero == -1){
+                if(vers == ISectVersion1)
+                        zero = 1;
+                else
+                        zero = 0;
+        }
+
+        if(argc != 2)
+                usage();
+
+        name = argv[0];
+        file = argv[1];
+
+        if(nameok(name) < 0)
+                sysfatal("illegal name %s", name);
+
+        part = initpart(file, ORDWR|ODIRECT);
+        if(part == nil)
+                sysfatal("can't open partition %s: %r", file);
+
+        if(zero)
+                zeropart(part, blocksize);
+
+        is = newisect(part, vers, name, blocksize, setsize);
+        if(is == nil)
+                sysfatal("can't initialize new index: %r");
+
+        fprint(2, "fmtisect %s: %,d buckets of %,d entries, %,d bytes for index map\n",
+                file, is->blocks, is->buckmax, setsize);
+
+        if(wbisect(is) < 0)
+                fprint(2, "can't write back index section header for %s: %r\n", file);
+
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/srv/fns.h b/src/cmd/venti/srv/fns.h
t@@ -0,0 +1,206 @@
+/*
+ * sorted by 4,/^$/|sort -bd +1
+ */
+int                addarena(Arena *name);
+void                addstat(int, int);
+void                addstat2(int, int, int, int);
+ZBlock                *alloczblock(u32int size, int zeroed, uint alignment);
+Arena                *amapitoa(Index *index, u64int a, u64int *aa);
+u64int                arenadirsize(Arena *arena, u32int clumps);
+void                arenaupdate(Arena *arena, u32int size, u8int *score);
+void                backsumarena(Arena *arena);
+void        binstats(long (*fn)(Stats *s0, Stats *s1, void*), void *arg, long t0, long t1, Statbin *bin, int nbin);
+int                bloominit(Bloom*, vlong, uchar*);
+int                bucklook(u8int*, int, u8int*, int);
+u32int                buildbucket(Index *ix, IEStream *ies, IBucket *ib, uint);
+void                checkdcache(void);
+void                checklumpcache(void);
+int                clumpinfoeq(ClumpInfo *c, ClumpInfo *d);
+int                clumpinfoeq(ClumpInfo *c, ClumpInfo *d);
+u32int                clumpmagic(Arena *arena, u64int aa);
+uint                countbits(uint n);
+int                delarena(Arena *arena);
+void                delaykickicache(void);
+void                delaykickround(Round*);
+void                delaykickroundproc(void*);
+void                dirtydblock(DBlock*, int);
+AState        diskstate(void);
+void                *emalloc(ulong);
+void                *erealloc(void *, ulong);
+char                *estrdup(char*);
+void                *ezmalloc(ulong);
+Arena                *findarena(char *name);
+int                flushciblocks(Arena *arena);
+void                flushdcache(void);
+void                flushicache(void);
+void                flushqueue(void);
+void                fmtzbinit(Fmt *f, ZBlock *b);
+void                freearena(Arena *arena);
+void                freearenapart(ArenaPart *ap, int freearenas);
+void                freeiestream(IEStream *ies);
+void                freeifile(IFile *f);
+void                freeisect(ISect *is);
+void                freeindex(Index *index);
+void                freepart(Part *part);
+void                freezblock(ZBlock *b);
+DBlock                *_getdblock(Part *part, u64int addr, int mode, int load);
+DBlock                *getdblock(Part *part, u64int addr, int mode);
+u32int                hashbits(u8int *score, int nbits);
+int                httpdinit(char *address, char *webroot);
+int                iaddrcmp(IAddr *ia1, IAddr *ia2);
+IEntry*        icachedirty(u32int, u32int, u64int);
+void                icacheclean(IEntry*);
+int                ientrycmp(const void *vie1, const void *vie2);
+char                *ifileline(IFile *f);
+int                ifilename(IFile *f, char *dst);
+int                ifileu32int(IFile *f, u32int *r);
+int                inbloomfilter(Bloom*, u8int*);
+int                indexsect(Index *ix, u8int *score);
+int                indexsect0(Index *ix, u32int buck);
+Arena                *initarena(Part *part, u64int base, u64int size, u32int blocksize);
+ArenaPart        *initarenapart(Part *part);
+int                initarenasum(void);
+void                initbloomfilter(Index*);
+void                initdcache(u32int mem);
+void                initicache(int bits, int depth);
+void                initicachewrite(void);
+IEStream        *initiestream(Part *part, u64int off, u64int clumps, u32int size);
+ISect                *initisect(Part *part);
+Index                *initindex(char *name, ISect **sects, int n);
+void                initlumpcache(u32int size, u32int nblocks);
+int                initlumpqueues(int nq);
+Part*                initpart(char *name, int mode);
+void                initround(Round*, char*, int);
+int                initventi(char *config, Config *conf);
+void                insertlump(Lump *lump, Packet *p);
+int                insertscore(u8int *score, IAddr *ia, int write);
+void                kickdcache(void);
+void                kickicache(void);
+void                kickround(Round*, int wait);
+ZBlock                *loadclump(Arena *arena, u64int aa, int blocks, Clump *cl, u8int *score, int verify);
+DBlock        *loadibucket(Index *index, u8int *score, ISect **is, u32int *buck, IBucket *ib);
+int                loadientry(Index *index, u8int *score, int type, IEntry *ie);
+void                logerr(int severity, char *fmt, ...);
+Lump                *lookuplump(u8int *score, int type);
+int                lookupscore(u8int *score, int type, IAddr *ia, int *rac);
+int                maparenas(AMap *am, Arena **arenas, int n, char *what);
+void                markbloomfilter(Bloom*, u8int*);
+uint                msec(void);
+int                namecmp(char *s, char *t);
+void                namecp(char *dst, char *src);
+int                nameok(char *name);
+Arena                *newarena(Part *part, u32int, char *name, u64int base, u64int size, u32int blocksize);
+ArenaPart        *newarenapart(Part *part, u32int blocksize, u32int tabsize);
+ISect                *newisect(Part *part, u32int vers, char *name, u32int blocksize, u32int tabsize);
+Index                *newindex(char *name, ISect **sects, int n);
+u32int                now(void);
+int                okamap(AMap *am, int n, u64int start, u64int stop, char *what);
+int                okibucket(IBucket*, ISect*);
+int                outputamap(Fmt *f, AMap *am, int n);
+int                outputindex(Fmt *f, Index *ix);
+int                packarena(Arena *arena, u8int *buf);
+int                packarenahead(ArenaHead *head, u8int *buf);
+int                packarenapart(ArenaPart *as, u8int *buf);
+void                packbloomhead(Bloom*, u8int*);
+int                packclump(Clump *c, u8int *buf, u32int);
+void                packclumpinfo(ClumpInfo *ci, u8int *buf);
+void                packibucket(IBucket *b, u8int *buf, u32int magic);
+void                packientry(IEntry *i, u8int *buf);
+int                packisect(ISect *is, u8int *buf);
+void                packmagic(u32int magic, u8int *buf);
+ZBlock                *packet2zblock(Packet *p, u32int size);
+int                parseamap(IFile *f, AMapN *amn);
+int                parseindex(IFile *f, Index *ix);
+void                partblocksize(Part *part, u32int blocksize);
+int                partifile(IFile *f, Part *part, u64int start, u32int size);
+void                printarenapart(int fd, ArenaPart *ap);
+void                printarena(int fd, Arena *arena);
+void                printindex(int fd, Index *ix);
+void                printstats(void);
+void                putdblock(DBlock *b);
+void                putlump(Lump *b);
+int                queuewrite(Lump *b, Packet *p, int creator, uint ms);
+u32int                readarena(Arena *arena, u64int aa, u8int *buf, long n);
+int                readarenamap(AMapN *amn, Part *part, u64int base, u32int size);
+Bloom        *readbloom(Part*);
+int                readclumpinfo(Arena *arena, int clump, ClumpInfo *ci);
+int                readclumpinfos(Arena *arena, int clump, ClumpInfo *cis, int n);
+ZBlock                *readfile(char *name);
+int                readifile(IFile *f, char *name);
+Packet                *readlump(u8int *score, int type, u32int size, int *cached);
+int                readpart(Part *part, u64int addr, u8int *buf, u32int n);
+int                runconfig(char *config, Config*);
+int                scorecmp(u8int *, u8int *);
+void                scoremem(u8int *score, u8int *buf, int size);
+void                setatailstate(AState*);
+void                setdcachestate(AState*);
+void                seterr(int severity, char *fmt, ...);
+void                setstat(int, long);
+void                settrace(char *type);
+u64int                sortrawientries(Index *ix, Part *tmp, u64int *tmpoff, Bloom *bloom);
+void                startbloomproc(Bloom*);
+Memimage*        statgraph(Graph *g);
+void                statsinit(void);
+int                storeclump(Index *index, ZBlock *b, u8int *score, int type, u32int creator, IAddr *ia);
+int                storeientry(Index *index, IEntry *m);
+int                strscore(char *s, u8int *score);
+int                stru32int(char *s, u32int *r);
+int                stru64int(char *s, u64int *r);
+void                sumarena(Arena *arena);
+int                syncarena(Arena *arena, u64int start, u32int n, int zok, int fix);
+int                syncarenaindex(Index *ix, Arena *arena, u32int clump, u64int a, int fix, int *pflush, int check);
+int                syncindex(Index *ix, int fix, int mustflushicache, int check);
+void                trace(char *type, char*, ...);
+void                traceinit(void);
+int                u64log2(u64int v);
+u64int                unittoull(char *s);
+int                unpackarena(Arena *arena, u8int *buf);
+int                unpackarenahead(ArenaHead *head, u8int *buf);
+int                unpackarenapart(ArenaPart *as, u8int *buf);
+int                unpackbloomhead(Bloom*, u8int*);
+int                unpackclump(Clump *c, u8int *buf, u32int);
+void                unpackclumpinfo(ClumpInfo *ci, u8int *buf);
+void                unpackibucket(IBucket *b, u8int *buf, u32int magic);
+void                unpackientry(IEntry *i, u8int *buf);
+int                unpackisect(ISect *is, u8int *buf);
+u32int                unpackmagic(u8int *buf);
+void                ventifmtinstall(void);
+void                vtloghdump(Hio*, VtLog*);
+void                vtloghlist(Hio*);
+int                vtproc(void(*)(void*), void*);
+int                vttypevalid(int type);
+void                waitforkick(Round*);
+int                wbarena(Arena *arena);
+int                wbarenahead(Arena *arena);
+int                wbarenamap(AMap *am, int n, Part *part, u64int base, u64int size);
+int                wbarenapart(ArenaPart *ap);
+void                wbbloomhead(Bloom*);
+int                wbisect(ISect *is);
+int                wbindex(Index *ix);
+int                whackblock(u8int *dst, u8int *src, int ssize);
+u64int                writeaclump(Arena *a, Clump *c, u8int *clbuf, u64int, u64int*);
+u32int                writearena(Arena *arena, u64int aa, u8int *clbuf, u32int n);
+int                writebloom(Bloom*);
+int                writeclumpinfo(Arena *arean, int clump, ClumpInfo *ci);
+int                writepng(Hio*, Memimage*);
+u64int                writeiclump(Index *ix, Clump *c, u8int *clbuf, u64int*);
+int                writelump(Packet *p, u8int *score, int type, u32int creator, uint ms);
+int                writepart(Part *part, u64int addr, u8int *buf, u32int n);
+int                writeqlump(Lump *u, Packet *p, int creator, uint ms);
+Packet                *zblock2packet(ZBlock *zb, u32int size);
+void                zeropart(Part *part, int blocksize);
+
+/*
+#pragma        varargck        argpos        sysfatal                1
+#pragma        varargck        argpos        logerr                2
+#pragma        varargck        argpos        SetErr                2
+*/
+
+#define scorecmp(h1,h2)                memcmp((h1),(h2),VtScoreSize)
+#define scorecp(h1,h2)                memmove((h1),(h2),VtScoreSize)
+
+#define MK(t)                        ((t*)emalloc(sizeof(t)))
+#define MKZ(t)                        ((t*)ezmalloc(sizeof(t)))
+#define MKN(t,n)                ((t*)emalloc((n)*sizeof(t)))
+#define MKNZ(t,n)                ((t*)ezmalloc((n)*sizeof(t)))
+#define MKNA(t,at,n)                ((t*)emalloc(sizeof(t) + (n)*sizeof(at)))
diff --git a/src/cmd/venti/srv/graph.c b/src/cmd/venti/srv/graph.c
t@@ -0,0 +1,202 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+enum
+{
+        Top = 1,
+        Bottom = 1,
+        Left = 40,
+        Right = 0,
+        MinWidth = Left+Right+2,
+        MinHeight = Top+Bottom+2,
+        DefaultWidth = Left+Right+500,
+        DefaultHeight = Top+Bottom+40
+};
+
+QLock memdrawlock;
+static Memsubfont *smallfont;
+static Memimage *black;
+static Memimage *blue;
+static Memimage *red;
+static Memimage *lofill[6];
+static Memimage *hifill[6];
+static Memimage *grid;
+
+static ulong fill[] = {
+        0xFFAAAAFF,        0xBB5D5DFF,        /* peach */
+        DPalegreygreen, DPurpleblue,        /* aqua */
+        DDarkyellow, DYellowgreen,        /* yellow */
+        DMedgreen, DDarkgreen,                /* green */
+        0x00AAFFFF, 0x0088CCFF,        /* blue */
+        0xCCCCCCFF, 0x888888FF,        /* grey */
+};
+
+Memimage*
+allocrepl(ulong color)
+{
+        Memimage *m;
+        
+        m = allocmemimage(Rect(0,0,1,1), RGB24);
+        memfillcolor(m, color);
+        m->flags |= Frepl;
+        m->clipr = Rect(-1000000, -1000000, 1000000, 1000000);
+        return m;
+}
+
+static void
+ginit(void)
+{
+        static int first = 1;
+        int i;
+        
+        if(!first)
+                return;
+                
+        first = 0;
+        memimageinit();
+        smallfont = openmemsubfont(unsharp("#9/font/lucidasans/lstr.10"));
+        black = memblack;
+        blue = allocrepl(DBlue);
+        red = allocrepl(DRed);
+        grid = allocrepl(0x77777777);
+        for(i=0; i= valmax)
+                val = valmax;
+        if(valmax == valmin)
+                valmax++;
+        return ptmin + (vlong)(val-valmin)*(ptmax-ptmin)/(valmax-valmin);
+}
+
+Memimage*
+statgraph(Graph *g)
+{
+        int i, lastlo, nbin, x, lo, hi, min, max, first;
+        Memimage *m;
+        Rectangle r;
+        Statbin *b, bin[2000];        /* 32 kB, but whack is worse */
+
+        needstack(8192);        /* double check that bin didn't kill us */
+        
+        if(g->wid <= MinWidth)
+                g->wid = DefaultWidth;
+        if(g->ht <= MinHeight)
+                g->ht = DefaultHeight;
+        if(g->wid > nelem(bin))
+                g->wid = nelem(bin);
+        if(g->fill < 0)
+                g->fill = ((uint)g->arg>>8)%nelem(lofill);
+        if(g->fill > nelem(lofill))
+                g->fill %= nelem(lofill);
+        
+        nbin = g->wid - (Left+Right);
+        binstats(g->fn, g->arg, g->t0, g->t1, bin, nbin);
+
+        /*
+         * compute bounds
+         */
+        min = g->min;
+        max = g->max;
+        if(min < 0 || max <= min){
+                min = max = 0;
+                first = 1;
+                for(i=0; insamp == 0)
+                                continue;
+                        if(first || b->min < min)
+                                min = b->min;
+                        if(first || b->max > max)
+                                max = b->max;
+                        first = 0;
+                }
+        }
+
+        qlock(&memdrawlock);
+        ginit();
+        if(smallfont==nil || black==nil || blue==nil || red==nil || hifill==nil || lofill==nil){
+                werrstr("graphics initialization failed");
+                qunlock(&memdrawlock);
+                return nil;
+        }
+
+        /* fresh image */
+        m = allocmemimage(Rect(0,0,g->wid,g->ht), ABGR32);
+        if(m == nil){
+                qunlock(&memdrawlock);
+                return nil;
+        }
+        r = Rect(Left, Top, g->wid-Right, g->ht-Bottom);
+        memfillcolor(m, DTransparent);
+        
+        /* x axis */
+        memimagedraw(m, Rect(r.min.x, r.max.y, r.max.x, r.max.y+1), black, ZP, memopaque, ZP, S);
+
+        /* y labels */
+        drawlabel(m, r.min, max);
+        if(min != 0)
+                drawlabel(m, Pt(r.min.x, r.max.y-smallfont->height), min);
+        
+        /* actual data */
+        lastlo = -1;
+        for(i=0; insamp == 0)
+                        continue;
+                lo = scalept(b->min, min, max, r.max.y, r.min.y);
+                hi = scalept(b->max, min, max, r.max.y, r.min.y);
+                x = r.min.x+i;
+                hi-=2;
+                if(0)
+                if(lastlo != -1){
+                        if(lastlo < lo)
+                                memimagedraw(m, Rect(x-1, lastlo, x, lo), hifill[g->fill], ZP, memopaque, ZP, S);
+                        else if(lastlo > lo)
+                                memimagedraw(m, Rect(x-1, lo, x, lastlo), hifill[g->fill], ZP, memopaque, ZP, S);
+                }
+                memimagedraw(m, Rect(x, hi, x+1,lo), hifill[g->fill], ZP, memopaque, ZP, S);
+                memimagedraw(m, Rect(x, lo, x+1, r.max.y), lofill[g->fill], ZP, memopaque, ZP, S);
+                lastlo = lo;
+        }
+
+        if(bin[nbin-1].nsamp)
+                drawlabel(m, Pt(r.max.x, r.min.y+(Dy(r)-smallfont->height)/2), bin[nbin-1].avg);
+        qunlock(&memdrawlock);
+        return m;
+}
diff --git a/src/cmd/venti/srv/httpd.c b/src/cmd/venti/srv/httpd.c
t@@ -0,0 +1,988 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+#include "xml.h"
+
+typedef struct HttpObj        HttpObj;
+extern QLock memdrawlock;
+
+enum
+{
+        ObjNameSize        = 64,
+        MaxObjs                = 16
+};
+
+struct HttpObj
+{
+        char        name[ObjNameSize];
+        int        (*f)(HConnect*);
+};
+
+static HttpObj        objs[MaxObjs];
+
+static char *webroot;
+
+static        void                listenproc(void*);
+static        int                estats(HConnect *c);
+static        int                dindex(HConnect *c);
+static        int                xindex(HConnect *c);
+static        int                xlog(HConnect *c);
+static        int                sindex(HConnect *c);
+static        int                hicacheflush(HConnect *c);
+static        int                hdcacheflush(HConnect *c);
+static        int                notfound(HConnect *c);
+static        int                httpdobj(char *name, int (*f)(HConnect*));
+static        int                xgraph(HConnect *c);
+static        int                xset(HConnect *c);
+static        int                fromwebdir(HConnect *c);
+
+int
+httpdinit(char *address, char *dir)
+{
+        fmtinstall('D', hdatefmt);
+/*        fmtinstall('H', httpfmt); */
+        fmtinstall('U', hurlfmt);
+
+        if(address == nil)
+                address = "tcp!*!http";
+        webroot = dir;
+        
+        httpdobj("/stats", estats);
+        httpdobj("/index", dindex);
+        httpdobj("/storage", sindex);
+        httpdobj("/xindex", xindex);
+        httpdobj("/flushicache", hicacheflush);
+        httpdobj("/flushdcache", hdcacheflush);
+        httpdobj("/graph/", xgraph);
+        httpdobj("/set/", xset);
+        httpdobj("/log", xlog);
+        httpdobj("/log/", xlog);
+
+        if(vtproc(listenproc, address) < 0)
+                return -1;
+        return 0;
+}
+
+static int
+httpdobj(char *name, int (*f)(HConnect*))
+{
+        int i;
+
+        if(name == nil || strlen(name) >= ObjNameSize)
+                return -1;
+        for(i = 0; i < MaxObjs; i++){
+                if(objs[i].name[0] == '\0'){
+                        strcpy(objs[i].name, name);
+                        objs[i].f = f;
+                        return 0;
+                }
+                if(strcmp(objs[i].name, name) == 0)
+                        return -1;
+        }
+        return -1;
+}
+
+static HConnect*
+mkconnect(void)
+{
+        HConnect *c;
+
+        c = mallocz(sizeof(HConnect), 1);
+        if(c == nil)
+                sysfatal("out of memory");
+        c->replog = nil;
+        c->hpos = c->header;
+        c->hstop = c->header;
+        return c;
+}
+
+void httpproc(void*);
+
+static void
+listenproc(void *vaddress)
+{
+        HConnect *c;
+        char *address, ndir[NETPATHLEN], dir[NETPATHLEN];
+        int ctl, nctl, data;
+
+//sleep(1000);        /* let strace find us */
+
+        address = vaddress;
+        ctl = announce(address, dir);
+        if(ctl < 0){
+                fprint(2, "venti: httpd can't announce on %s: %r\n", address);
+                return;
+        }
+
+        if(0) print("announce ctl %d dir %s\n", ctl, dir);
+        for(;;){
+                /*
+                 *  wait for a call (or an error)
+                 */
+                nctl = listen(dir, ndir);
+                if(0) print("httpd listen %d %s...\n", nctl, ndir);
+                if(nctl < 0){
+                        fprint(2, "venti: httpd can't listen on %s: %r\n", address);
+                        return;
+                }
+
+                data = accept(ctl, ndir);
+                if(0) print("httpd accept %d...\n", data);
+                if(data < 0){
+                        fprint(2, "venti: httpd accept: %r\n");
+                        close(nctl);
+                        continue;
+                }
+                if(0) print("httpd close nctl %d\n", nctl);
+                close(nctl);
+                c = mkconnect();
+                hinit(&c->hin, data, Hread);
+                hinit(&c->hout, data, Hwrite);
+                vtproc(httpproc, c);
+        }
+}
+
+void
+httpproc(void *v)
+{
+        HConnect *c;
+        int ok, i, n;
+
+//sleep(1000);        /* let strace find us */
+        c = v;
+
+        for(;;){
+                /*
+                 * No timeout because the signal appears to hit every
+                 * proc, not just us.
+                 */
+                if(hparsereq(c, 0) < 0)
+                        break;
+
+                ok = -1;
+                for(i = 0; i < MaxObjs && objs[i].name[0]; i++){
+                        n = strlen(objs[i].name);
+                        if((objs[i].name[n-1] == '/' && strncmp(c->req.uri, objs[i].name, n) == 0)
+                        || (objs[i].name[n-1] != '/' && strcmp(c->req.uri, objs[i].name) == 0)){
+                                ok = (*objs[i].f)(c);
+                                goto found;
+                        }
+                }
+                ok = fromwebdir(c);
+        found:
+                if(c->head.closeit)
+                        ok = -1;
+                hreqcleanup(c);
+
+                if(ok < 0)
+                        break;
+        }
+        hreqcleanup(c);
+        close(c->hin.fd);
+        free(c);
+}
+
+static int
+percent(long v, long total)
+{
+        if(total == 0)
+                total = 1;
+        if(v < 1000*1000)
+                return (v * 100) / total;
+        total /= 100;
+        if(total == 0)
+                total = 1;
+        return v / total;
+}
+
+static int
+preq(HConnect *c)
+{
+        if(hparseheaders(c, 0) < 0)
+                return -1;
+        if(strcmp(c->req.meth, "GET") != 0
+        && strcmp(c->req.meth, "HEAD") != 0)
+                return hunallowed(c, "GET, HEAD");
+        if(c->head.expectother || c->head.expectcont)
+                return hfail(c, HExpectFail, nil);
+        return 0;
+}
+
+static int
+preqtype(HConnect *c, char *type)
+{
+        Hio *hout;
+        int r;
+
+        r = preq(c);
+        if(r < 0)
+                return r;
+
+        hout = &c->hout;
+        if(c->req.vermaj){
+                hokheaders(c);
+                hprint(hout, "Content-type: %s\r\n", type);
+                if(http11(c))
+                        hprint(hout, "Transfer-Encoding: chunked\r\n");
+                hprint(hout, "\r\n");
+        }
+
+        if(http11(c))
+                hxferenc(hout, 1);
+        else
+                c->head.closeit = 1;
+        return 0;
+}
+
+static int
+preqtext(HConnect *c)
+{
+        return preqtype(c, "text/plain");
+}
+
+static int
+notfound(HConnect *c)
+{
+        int r;
+
+        r = preq(c);
+        if(r < 0)
+                return r;
+        return hfail(c, HNotFound, c->req.uri);
+}
+
+struct {
+        char *ext;
+        char *type;
+} exttab[] = {
+        ".html",        "text/html",
+        ".txt",        "text/plain",
+        ".xml",        "text/xml",
+        ".png",        "image/png",
+        ".gif",        "image/gif",
+        0
+};
+
+static int
+fromwebdir(HConnect *c)
+{
+        char buf[4096], *p, *ext, *type;
+        int i, fd, n, defaulted;
+        Dir *d;
+        
+        if(webroot == nil || strstr(c->req.uri, ".."))
+                return notfound(c);
+        snprint(buf, sizeof buf-20, "%s/%s", webroot, c->req.uri+1);
+        defaulted = 0;
+reopen:
+        if((fd = open(buf, OREAD)) < 0)
+                return notfound(c);
+        d = dirfstat(fd);
+        if(d == nil){
+                close(fd);
+                return notfound(c);
+        }
+        if(d->mode&DMDIR){
+                if(!defaulted){
+                        defaulted = 1;
+                        strcat(buf, "/index.html");
+                        free(d);
+                        close(fd);
+                        goto reopen;
+                }
+                free(d);
+                return notfound(c);
+        }
+        free(d);
+        p = buf+strlen(buf);
+        type = "application/octet-stream";
+        for(i=0; exttab[i].ext; i++){
+                ext = exttab[i].ext;
+                if(p-strlen(ext) >= buf && strcmp(p-strlen(ext), ext) == 0){
+                        type = exttab[i].type;
+                        break;
+                }
+        }
+        if(preqtype(c, type) < 0){
+                close(fd);
+                return 0;
+        }
+        while((n = read(fd, buf, sizeof buf)) > 0)
+                if(hwrite(&c->hout, buf, n) < 0)
+                        break;
+        close(fd);
+        hflush(&c->hout);
+        return 0;
+}
+
+static struct
+{
+        char *name;
+        int *p;
+} namedints[] =
+{
+        "compress",        &compressblocks,
+        "devnull",        &writestodevnull,
+        "logging",        &ventilogging,
+        "stats",        &collectstats,
+        "icachesleeptime",        &icachesleeptime,
+        "arenasumsleeptime",        &arenasumsleeptime,
+        0
+};
+
+static int
+xset(HConnect *c)
+{
+        int i, nf, r;
+        char *f[10], *s;
+
+        s = estrdup(c->req.uri);
+        nf = getfields(s+strlen("/set/"), f, nelem(f), 1, "/");
+
+        if(nf < 1)
+                return notfound(c);
+        for(i=0; namedints[i].name; i++){
+                if(strcmp(f[0], namedints[i].name) == 0){
+                        if(nf >= 2)
+                                *namedints[i].p = atoi(f[1]);
+                        r = preqtext(c);
+                        if(r < 0)
+                                return r;
+                        hprint(&c->hout, "%s = %d\n", f[0], *namedints[i].p);
+                        hflush(&c->hout);
+                        return 0;
+                }
+        }
+        return notfound(c);
+}
+
+static int
+estats(HConnect *c)
+{
+        Hio *hout;
+        int r;
+
+        r = preqtext(c);
+        if(r < 0)
+                return r;
+
+
+        hout = &c->hout;
+/*
+        hprint(hout, "lump writes=%,ld\n", stats.lumpwrites);
+        hprint(hout, "lump reads=%,ld\n", stats.lumpreads);
+        hprint(hout, "lump cache read hits=%,ld\n", stats.lumphit);
+        hprint(hout, "lump cache read misses=%,ld\n", stats.lumpmiss);
+
+        hprint(hout, "clump disk writes=%,ld\n", stats.clumpwrites);
+        hprint(hout, "clump disk bytes written=%,lld\n", stats.clumpbwrites);
+        hprint(hout, "clump disk bytes compressed=%,lld\n", stats.clumpbcomp);
+        hprint(hout, "clump disk reads=%,ld\n", stats.clumpreads);
+        hprint(hout, "clump disk bytes read=%,lld\n", stats.clumpbreads);
+        hprint(hout, "clump disk bytes uncompressed=%,lld\n", stats.clumpbuncomp);
+
+        hprint(hout, "clump directory disk writes=%,ld\n", stats.ciwrites);
+        hprint(hout, "clump directory disk reads=%,ld\n", stats.cireads);
+
+        hprint(hout, "index disk writes=%,ld\n", stats.indexwrites);
+        hprint(hout, "index disk reads=%,ld\n", stats.indexreads);
+        hprint(hout, "index disk bloom filter hits=%,ld %d%% falsemisses=%,ld %d%%\n",
+                stats.indexbloomhits,
+                percent(stats.indexbloomhits, stats.indexreads),
+                stats.indexbloomfalsemisses,
+                percent(stats.indexbloomfalsemisses, stats.indexreads));
+        hprint(hout, "bloom filter bits=%,ld of %,ld %d%%\n",
+                stats.bloomones, stats.bloombits, percent(stats.bloomones, stats.bloombits));
+        hprint(hout, "index disk reads for modify=%,ld\n", stats.indexwreads);
+        hprint(hout, "index disk reads for allocation=%,ld\n", stats.indexareads);
+        hprint(hout, "index block splits=%,ld\n", stats.indexsplits);
+
+        hprint(hout, "index cache lookups=%,ld\n", stats.iclookups);
+        hprint(hout, "index cache hits=%,ld %d%%\n", stats.ichits,
+                percent(stats.ichits, stats.iclookups));
+        hprint(hout, "index cache fills=%,ld %d%%\n", stats.icfills,
+                percent(stats.icfills, stats.iclookups));
+        hprint(hout, "index cache inserts=%,ld\n", stats.icinserts);
+
+        hprint(hout, "disk cache hits=%,ld\n", stats.pchit);
+        hprint(hout, "disk cache misses=%,ld\n", stats.pcmiss);
+        hprint(hout, "disk cache reads=%,ld\n", stats.pcreads);
+        hprint(hout, "disk cache bytes read=%,lld\n", stats.pcbreads);
+
+        hprint(hout, "disk cache writes=%,ld\n", stats.dirtydblocks);
+        hprint(hout, "disk cache writes absorbed=%,ld %d%%\n", stats.absorbedwrites,
+                percent(stats.absorbedwrites, stats.dirtydblocks));
+
+        hprint(hout, "disk cache flushes=%,ld\n", stats.dcacheflushes);
+        hprint(hout, "disk cache flush writes=%,ld (%,ld per flush)\n", 
+                stats.dcacheflushwrites,
+                stats.dcacheflushwrites/(stats.dcacheflushes ? stats.dcacheflushes : 1));
+
+        hprint(hout, "disk writes=%,ld\n", stats.diskwrites);
+        hprint(hout, "disk bytes written=%,lld\n", stats.diskbwrites);
+        hprint(hout, "disk reads=%,ld\n", stats.diskreads);
+        hprint(hout, "disk bytes read=%,lld\n", stats.diskbreads);
+*/
+
+        hflush(hout);
+        return 0;
+}
+
+static int
+sindex(HConnect *c)
+{
+        Hio *hout;
+        Index *ix;
+        Arena *arena;
+        vlong clumps, cclumps, uncsize, used, size;
+        int i, r, active;
+
+        r = preqtext(c);
+        if(r < 0)
+                return r;
+        hout = &c->hout;
+
+        ix = mainindex;
+
+        hprint(hout, "index=%s\n", ix->name);
+
+        active = 0;
+        clumps = 0;
+        cclumps = 0;
+        uncsize = 0;
+        used = 0;
+        size = 0;
+        for(i = 0; i < ix->narenas; i++){
+                arena = ix->arenas[i];
+                if(arena != nil && arena->memstats.clumps != 0){
+                        active++;
+                        clumps += arena->memstats.clumps;
+                        cclumps += arena->memstats.cclumps;
+                        uncsize += arena->memstats.uncsize;
+                        used += arena->memstats.used;
+                }
+                size += arena->size;
+        }
+        hprint(hout, "total arenas=%,d active=%,d\n", ix->narenas, active);
+        hprint(hout, "total space=%,lld used=%,lld\n", size, used + clumps * ClumpInfoSize);
+        hprint(hout, "clumps=%,lld compressed clumps=%,lld data=%,lld compressed data=%,lld\n",
+                clumps, cclumps, uncsize, used - clumps * ClumpSize);
+        hflush(hout);
+        return 0;
+}
+
+static void
+darena(Hio *hout, Arena *arena)
+{
+        hprint(hout, "arena='%s' on %s at [%lld,%lld)\n\tversion=%d created=%d modified=%d",
+                arena->name, arena->part->name, arena->base, arena->base + arena->size + 2 * arena->blocksize,
+                arena->version, arena->ctime, arena->wtime);
+        if(arena->memstats.sealed)
+                hprint(hout, " mem=sealed");
+        if(arena->diskstats.sealed)
+                hprint(hout, " disk=sealed");
+        hprint(hout, "\n");
+        if(scorecmp(zeroscore, arena->score) != 0)
+                hprint(hout, "\tscore=%V\n", arena->score);
+
+        hprint(hout, "\tmem: clumps=%d compressed clumps=%d data=%,lld compressed data=%,lld storage=%,lld\n",
+                arena->memstats.clumps, arena->memstats.cclumps, arena->memstats.uncsize,
+                arena->memstats.used - arena->memstats.clumps * ClumpSize,
+                arena->memstats.used + arena->memstats.clumps * ClumpInfoSize);
+        hprint(hout, "\tdisk: clumps=%d compressed clumps=%d data=%,lld compressed data=%,lld storage=%,lld\n",
+                arena->diskstats.clumps, arena->diskstats.cclumps, arena->diskstats.uncsize,
+                arena->diskstats.used - arena->diskstats.clumps * ClumpSize,
+                arena->diskstats.used + arena->diskstats.clumps * ClumpInfoSize);
+}
+
+static int
+hicacheflush(HConnect *c)
+{
+        Hio *hout;
+        int r;
+
+        r = preqtext(c);
+        if(r < 0)
+                return r;
+        hout = &c->hout;
+
+        flushicache();
+        hprint(hout, "flushed icache\n");
+        hflush(hout);
+        return 0;
+}
+
+static int
+hdcacheflush(HConnect *c)
+{
+        Hio *hout;
+        int r;
+
+        r = preqtext(c);
+        if(r < 0)
+                return r;
+        hout = &c->hout;
+
+        flushdcache();
+        hprint(hout, "flushed dcache\n");
+        hflush(hout);
+        return 0;
+}
+
+static int
+dindex(HConnect *c)
+{
+        Hio *hout;
+        Index *ix;
+        int i, r;
+
+        r = preqtext(c);
+        if(r < 0)
+                return r;
+        hout = &c->hout;
+
+
+        ix = mainindex;
+        hprint(hout, "index=%s version=%d blocksize=%d tabsize=%d\n",
+                ix->name, ix->version, ix->blocksize, ix->tabsize);
+        hprint(hout, "\tbuckets=%d div=%d\n", ix->buckets, ix->div);
+        for(i = 0; i < ix->nsects; i++)
+                hprint(hout, "\tsect=%s for buckets [%lld,%lld) buckmax=%d\n", ix->smap[i].name, ix->smap[i].start, ix->smap[i].stop, ix->sects[i]->buckmax);
+        for(i = 0; i < ix->narenas; i++){
+                if(ix->arenas[i] != nil && ix->arenas[i]->memstats.clumps != 0){
+                        hprint(hout, "arena=%s at index [%lld,%lld)\n\t", ix->amap[i].name, ix->amap[i].start, ix->amap[i].stop);
+                        darena(hout, ix->arenas[i]);
+                }
+        }
+        hflush(hout);
+        return 0;
+}
+
+typedef struct Arg Arg;
+struct Arg
+{
+        int index;
+        int index2;
+};
+
+static long
+rawgraph(Stats *s, Stats *t, void *va)
+{
+        Arg *a;
+
+        a = va;
+        return t->n[a->index];
+}
+
+static long
+diffgraph(Stats *s, Stats *t, void *va)
+{
+        Arg *a;
+
+        a = va;
+        return t->n[a->index] - s->n[a->index];
+}
+
+static long
+pctgraph(Stats *s, Stats *t, void *va)
+{
+        Arg *a;
+
+        a = va;
+        return percent(t->n[a->index], t->n[a->index2]);
+}
+
+static long
+pctdiffgraph(Stats *s, Stats *t, void *va)
+{
+        Arg *a;
+
+        a = va;
+        return percent(t->n[a->index]-s->n[a->index], t->n[a->index2]-s->n[a->index2]);
+}
+
+static long
+netbw(Stats *s)
+{
+        ulong *n;
+
+        n = s->n;
+        return n[StatRpcReadBytes]+n[StatRpcWriteBytes];        /* not exactly right */
+}
+
+static long
+diskbw(Stats *s)
+{
+        ulong *n;
+
+        n = s->n;
+        return n[StatApartReadBytes]+n[StatApartWriteBytes]        
+                + n[StatIsectReadBytes]+n[StatIsectWriteBytes]
+                + n[StatSumReadBytes];
+}
+
+static long
+iobw(Stats *s)
+{
+        return netbw(s)+diskbw(s);
+}
+
+static long
+diskgraph(Stats *s, Stats *t, void *va)
+{
+        USED(va);
+        return diskbw(t)-diskbw(s);
+}
+
+static long
+netgraph(Stats *s, Stats *t, void *va)
+{
+        USED(va);
+        return netbw(t)-netbw(s);
+}
+
+static long
+iograph(Stats *s, Stats *t, void *va)
+{
+        USED(va);
+        return iobw(t)-iobw(s);
+}
+
+
+static char* graphname[] =
+{
+        "rpctotal",
+        "rpcread",
+        "rpcreadok",
+        "rpcreadfail",
+        "rpcreadbyte",
+        "rpcreadtime",
+        "rpcreadcached",
+        "rpcreadcachedtime",
+        "rpcreaduncached",
+        "rpcreaduncachedtime",
+        "rpcwrite",
+        "rpcwritenew",
+        "rpcwriteold",
+        "rpcwritefail",
+        "rpcwritebyte",
+        "rpcwritetime",
+        "rpcwritenewtime",
+        "rpcwriteoldtime",
+
+        "lcachehit",
+        "lcachemiss",
+        "lcachelookup",
+        "lcachewrite",
+        "lcachesize",
+        "lcachestall",
+        "lcachelookuptime",
+        
+        "dcachehit",
+        "dcachemiss",
+        "dcachelookup",
+        "dcacheread",
+        "dcachewrite",
+        "dcachedirty",
+        "dcachesize",
+        "dcacheflush",
+        "dcachestall",
+        "dcachelookuptime",
+
+        "dblockstall",
+        "lumpstall",
+
+        "icachehit",
+        "icachemiss",
+        "icachelookup",
+        "icachewrite",
+        "icachefill",
+        "icacheprefetch",
+        "icachedirty",
+        "icachesize",
+        "icacheflush",
+        "icachestall",
+        "icachelookuptime",
+
+        "bloomhit",
+        "bloommiss",
+        "bloomfalsemiss",
+        "bloomlookup",
+        "bloomones",
+        "bloombits",
+        "bloomlookuptime",
+
+        "apartread",
+        "apartreadbyte",
+        "apartwrite",
+        "apartwritebyte",
+
+        "isectread",
+        "isectreadbyte",
+        "isectwrite",
+        "isectwritebyte",
+
+        "sumread",
+        "sumreadbyte",
+};
+
+static int
+findname(char *s)
+{
+        int i;
+
+        for(i=0; ifn, g->arg, g->t0, g->t1, bin, nbin);
+
+        hprint(io, "stats\n\n");
+        for(i=0; insamp, b->min, b->max, b->avg);
+        }
+}
+
+static int
+xgraph(HConnect *c)
+{
+        char *f[20], *s;
+        Hio *hout;
+        Memimage *m;
+        int i, nf, dotext;
+        Graph g;
+        Arg arg;
+
+        s = estrdup(c->req.uri);
+if(0) fprint(2, "graph %s\n" ,s);
+        memset(&g, 0, sizeof g);
+        nf = getfields(s+strlen("/graph/"), f, nelem(f), 1, "/");
+        if(nf < 1)
+                goto notfound;
+        if((arg.index = findname(f[0])) == -1 && strcmp(f[0], "*") != 0)
+                goto notfound;
+        g.arg = &arg;
+        g.t0 = -120;
+        g.t1 = 0;
+        g.min = -1;
+        g.max = -1;
+        g.fn = rawgraph;
+        g.wid = -1;
+        g.ht = -1;
+        dotext = 0;
+        g.fill = -1;
+        for(i=1; ihout, &g);
+                hflush(&c->hout);
+                return 0;
+        }
+
+        m = statgraph(&g);
+        if(m == nil)
+                goto notfound;
+
+        if(preqtype(c, "image/png") < 0)
+                return -1;
+        hout = &c->hout;
+        writepng(hout, m);
+        qlock(&memdrawlock);
+        freememimage(m);
+        qunlock(&memdrawlock);
+        hflush(hout);
+        free(s);
+        return 0;
+
+notfound:
+        free(s);
+        return notfound(c);
+}
+
+static int
+xloglist(HConnect *c)
+{
+        if(preqtype(c, "text/html") < 0)
+                return -1;
+        vtloghlist(&c->hout);
+        hflush(&c->hout);
+        return 0;
+}
+
+static int
+xlog(HConnect *c)
+{
+        char *name;
+        VtLog *l;
+
+        if(strcmp(c->req.uri, "/log") == 0 || strcmp(c->req.uri, "/log/") == 0)
+                return xloglist(c);
+        if(strncmp(c->req.uri, "/log/", 5) != 0)
+                return notfound(c);
+        name = c->req.uri + strlen("/log/");
+        l = vtlogopen(name, 0);
+        if(l == nil)
+                return notfound(c);
+        if(preqtype(c, "text/html") < 0){
+                vtlogclose(l);
+                return -1;
+        }
+        vtloghdump(&c->hout, l);
+        vtlogclose(l);
+        hflush(&c->hout);
+        return 0;
+}
+
+static int
+xindex(HConnect *c)
+{
+        if(preqtype(c, "text/xml") < 0)
+                return -1;
+        xmlindex(&c->hout, mainindex, "index", 0);
+        hflush(&c->hout);
+        return 0;
+}
+
+void
+xmlindent(Hio *hout, int indent)
+{
+        int i;
+
+        for(i = 0; i < indent; i++)
+                hputc(hout, '\t');
+}
+
+void
+xmlaname(Hio *hout, char *v, char *tag)
+{
+        hprint(hout, " %s=\"%s\"", tag, v);
+}
+
+void
+xmlscore(Hio *hout, u8int *v, char *tag)
+{
+        if(scorecmp(zeroscore, v) == 0)
+                return;
+        hprint(hout, " %s=\"%V\"", tag, v);
+}
+
+void
+xmlsealed(Hio *hout, int v, char *tag)
+{
+        if(!v)
+                return;
+        hprint(hout, " %s=\"yes\"", tag);
+}
+
+void
+xmlu32int(Hio *hout, u32int v, char *tag)
+{
+        hprint(hout, " %s=\"%ud\"", tag, v);
+}
+
+void
+xmlu64int(Hio *hout, u64int v, char *tag)
+{
+        hprint(hout, " %s=\"%llud\"", tag, v);
+}
+
+void
+vtloghdump(Hio *h, VtLog *l)
+{
+        int i;
+        VtLogChunk *c;
+        char *name;
+        
+        name = l ? l->name : "<nil>";
+
+fprint(2, "hdump xfer %d\n", h->xferenc);
+        hprint(h, "\n");
+        hprint(h, "Venti Server Log: %s\n", name);
+        hprint(h, "\n");
+        hprint(h, "Venti Server Log: %s\n

\n", name); + + if(l){ + c = l->w; + for(i=0; inchunk; i++){ + if(++c == l->chunk+l->nchunk) + c = l->chunk; + hwrite(h, c->p, c->wp-c->p); + } + } + hprint(h, "\n"); +} + +static int +strpcmp(const void *va, const void *vb) +{ + return strcmp(*(char**)va, *(char**)vb); +} + +void +vtloghlist(Hio *h) +{ + char **p; + int i, n; + + hprint(h, "\n"); + hprint(h, "Venti Server Logs\n"); + hprint(h, "\n"); + hprint(h, "Venti Server Logs\n

\n"); + + p = vtlognames(&n); + qsort(p, n, sizeof(p[0]), strpcmp); + for(i=0; i%s
\n", p[i], p[i]); + vtfree(p); + hprint(h, "\n"); +}

diff --git a/src/cmd/venti/srv/icache.c b/src/cmd/venti/srv/icache.c
t@@ -0,0 +1,348 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+typedef struct ICache ICache;
+struct ICache
+{
+        QLock        lock;                        /* locks hash table & all associated data */
+        Rendez        full;
+        IEntry        **heads;                /* heads of all the hash chains */
+        int        bits;                        /* bits to use for indexing heads */
+        u32int        size;                        /* number of heads; == 1 << bits, should be < entries */
+        IEntry        *base;                        /* all allocated hash table entries */
+        u32int        entries;                /* elements in base */
+        IEntry        *dirty;                /* chain of dirty elements */
+        u32int        ndirty;
+        u32int        maxdirty;
+        u32int        unused;                        /* index of first unused element in base */
+        u32int        stolen;                        /* last head from which an element was stolen */
+
+        Arena        *last[4];
+        Arena        *lastload;
+        int                nlast;
+};
+
+static ICache icache;
+
+static IEntry        *icachealloc(IAddr *ia, u8int *score);
+
+/*
+ * bits is the number of bits in the icache hash table
+ * depth is the average depth
+ * memory usage is about (1<>= (32 - bits);
+        return v;
+}
+
+static void
+loadarenaclumps(Arena *arena, u64int aa)
+{
+        ulong i;
+        ClumpInfo ci;
+        IAddr ia;
+
+fprint(2, "seed index cache with arena @%llud, (map %llud), %d clumps\n", arena->base, aa, arena->memstats.clumps);
+        for(i=0; imemstats.clumps; i++){
+                if(readclumpinfo(arena, i, &ci) < 0)
+                        break;
+                ia.type = ci.type;
+                ia.size = ci.uncsize;
+                ia.blocks = (ci.size + ClumpSize + (1 << ABlockLog) - 1) >> ABlockLog;
+                ia.addr = aa;
+                aa += ClumpSize + ci.size;
+                if(ia.type != VtCorruptType)
+                        insertscore(ci.score, &ia, 0);
+        }
+}
+
+/*
+ZZZ need to think about evicting the correct IEntry,
+and writing back the wtime.
+ * look up data score in the index cache
+ * if this fails, pull it in from the disk index table, if it exists.
+ *
+ * must be called with the lump for this score locked
+ */
+int
+lookupscore(u8int *score, int type, IAddr *ia, int *rac)
+{
+        IEntry d, *ie, *last;
+        u32int h;
+        u64int aa;
+        Arena *load;
+        int i;
+        uint ms;
+
+        load = nil;
+        aa = 0;
+        ms = msec();
+        
+        trace(TraceLump, "lookupscore %V.%d", score, type);
+
+        qlock(&icache.lock);
+        h = hashbits(score, icache.bits);
+        last = nil;
+        for(ie = icache.heads[h]; ie != nil; ie = ie->next){
+                if(ie->ia.type == type && scorecmp(ie->score, score)==0){
+                        if(last != nil)
+                                last->next = ie->next;
+                        else
+                                icache.heads[h] = ie->next;
+                        addstat(StatIcacheHit, 1);
+                        ie->rac = 1;
+                        trace(TraceLump, "lookupscore incache");
+                        goto found;
+                }
+                last = ie;
+        }
+        addstat(StatIcacheMiss, 1);
+        qunlock(&icache.lock);
+
+        if(loadientry(mainindex, score, type, &d) < 0){
+                ms = msec() - ms;
+                addstat2(StatIcacheRead, 1, StatIcacheReadTime, ms);
+                return -1;
+        }
+
+        addstat(StatIcacheFill, 1);
+
+        trace(TraceLump, "lookupscore loaded");
+
+        /*
+         * no one else can load an entry for this score,
+         * since we have the overall score lock.
+         */
+        qlock(&icache.lock);
+
+        /*
+         * If we notice that all the hits are coming from one arena,
+         * load the table of contents for that arena into the cache.
+         */
+        ie = icachealloc(&d.ia, score);
+        icache.last[icache.nlast++%nelem(icache.last)] = amapitoa(mainindex, ie->ia.addr, &aa);
+        aa = ie->ia.addr - aa;        /* compute base addr of arena */
+        for(i=0; inext = icache.heads[h];
+        icache.heads[h] = ie;
+
+        *ia = ie->ia;
+        *rac = ie->rac;
+
+        qunlock(&icache.lock);
+
+        if(load){
+                trace(TraceProc, "preload 0x%llux", aa);
+                loadarenaclumps(load, aa);
+        }
+        ms = msec() - ms;
+        addstat2(StatIcacheRead, 1, StatIcacheReadTime, ms);
+
+        return 0;
+}
+
+/*
+ * insert a new element in the hash table.
+ */
+int
+insertscore(u8int *score, IAddr *ia, int write)
+{
+        IEntry *ie, se;
+        u32int h;
+
+        trace(TraceLump, "insertscore enter");
+        if(write)
+                addstat(StatIcacheWrite, 1);
+        else
+                addstat(StatIcachePrefetch, 1);
+
+        qlock(&icache.lock);
+        h = hashbits(score, icache.bits);
+
+        ie = icachealloc(ia, score);
+        if(write){
+                icache.ndirty++;
+                setstat(StatIcacheDirty, icache.ndirty);
+                delaykickicache();
+                ie->dirty = 1;
+        }
+        ie->next = icache.heads[h];
+        icache.heads[h] = ie;
+
+        se = *ie;
+        qunlock(&icache.lock);
+
+        if(write && icache.ndirty >= icache.maxdirty)
+                kickicache();
+
+        /*
+         * It's okay not to do this under icache.lock.
+         * Calling insertscore only happens when we hold
+         * the lump, meaning any searches for this block
+         * will hit in the lump cache until after we return.
+         */
+        markbloomfilter(mainindex->bloom, score);
+
+        return 0;
+}
+
+/*
+ * allocate a index cache entry which hasn't been used in a while.
+ * must be called with icache.lock locked
+ * if the score is already in the table, update the entry.
+ */
+static IEntry *
+icachealloc(IAddr *ia, u8int *score)
+{
+        int i;
+        IEntry *ie, *last, *clean, *lastclean;
+        u32int h;
+
+        h = hashbits(score, icache.bits);
+        last = nil;
+        for(ie = icache.heads[h]; ie != nil; ie = ie->next){
+                if(ie->ia.type == ia->type && scorecmp(ie->score, score)==0){
+                        if(last != nil)
+                                last->next = ie->next;
+                        else
+                                icache.heads[h] = ie->next;
+                        trace(TraceLump, "icachealloc hit");
+                        ie->rac = 1;
+                        return ie;
+                }
+                last = ie;
+        }
+
+        h = icache.unused;
+        if(h < icache.entries){
+                ie = &icache.base[h++];
+                icache.unused = h;
+                trace(TraceLump, "icachealloc unused");
+                goto Found;
+        }
+
+        h = icache.stolen;
+        for(i=0;; i++){
+                h++;
+                if(h >= icache.size)
+                        h = 0;
+                if(i == icache.size){
+                        trace(TraceLump, "icachealloc sleep");
+                        addstat(StatIcacheStall, 1);
+                        while(icache.ndirty == icache.entries){
+                                /*
+                                 * This is a bit suspect.  Kickicache will wake up the
+                                 * icachewritecoord, but if all the index entries are for
+                                 * unflushed disk blocks, icachewritecoord won't be
+                                 * able to do much.  It always rewakes everyone when
+                                 * it thinks it is done, though, so at least we'll go around
+                                 * the while loop again.  Also, if icachewritecoord sees
+                                 * that the disk state hasn't change at all since the last
+                                 * time around, it kicks the disk.  This needs to be
+                                 * rethought, but it shouldn't deadlock anymore.
+                                 */
+                                kickicache();
+                                rsleep(&icache.full);
+                        }
+                        addstat(StatIcacheStall, -1);
+                        i = 0;
+                }
+                lastclean = nil;
+                clean = nil;
+                last = nil;
+                for(ie=icache.heads[h]; ie; last=ie, ie=ie->next){
+                        if(!ie->dirty){
+                                clean = ie;
+                                lastclean = last;
+                        }
+                }
+                if(clean){
+                        if(lastclean)
+                                lastclean->next = clean->next;
+                        else
+                                icache.heads[h] = clean->next;
+                        clean->next = nil;
+                        icache.stolen = h;
+                        ie = clean;
+                        trace(TraceLump, "icachealloc steal");
+                        goto Found;
+                }
+        }
+
+Found:
+        ie->ia = *ia;
+        scorecp(ie->score, score);
+        ie->rac = 0;        
+        return ie;
+}
+
+IEntry*
+icachedirty(u32int lo, u32int hi, u64int limit)
+{
+        int i;
+        u32int h;
+        IEntry *ie, *dirty;
+
+        dirty = nil;
+        trace(TraceProc, "icachedirty enter");
+        qlock(&icache.lock);
+        for(i=0; inext)
+                if(ie->dirty && ie->ia.addr != 0 && ie->ia.addr < limit){
+                        h = hashbits(ie->score, 32);
+                        if(lo <= h && h <= hi){
+                                ie->nextdirty = dirty;
+                                dirty = ie;
+                        }
+                }
+        qunlock(&icache.lock);
+        trace(TraceProc, "icachedirty exit");
+        if(dirty == nil)
+                flushdcache();
+        return dirty;
+}
+
+void
+icacheclean(IEntry *ie)
+{
+        trace(TraceProc, "icachedirty enter");
+        qlock(&icache.lock);
+        for(; ie; ie=ie->nextdirty){
+                icache.ndirty--;
+                ie->dirty = 0;
+        }
+        setstat(StatIcacheDirty, icache.ndirty);
+        rwakeupall(&icache.full);
+        qunlock(&icache.lock);
+        trace(TraceProc, "icachedirty exit");
+}
+
diff --git a/src/cmd/venti/srv/icachewrite.c b/src/cmd/venti/srv/icachewrite.c
t@@ -0,0 +1,318 @@
+/*
+ * Write the dirty icache entries to disk.  Random seeks are
+ * so expensive that it makes sense to wait until we have
+ * a lot and then just make a sequential pass over the disk.
+ */
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+static void icachewriteproc(void*);
+static void icachewritecoord(void*);
+static IEntry *iesort(IEntry*);
+
+int icachesleeptime = 1000;        /* milliseconds */
+
+enum
+{
+        Bufsize = 8*1024*1024
+};
+
+typedef struct IWrite IWrite;
+struct IWrite
+{
+        Round round;
+        AState as;
+};
+
+static IWrite iwrite;
+
+void
+initicachewrite(void)
+{
+        int i;
+        Index *ix;
+
+        initround(&iwrite.round, "icache", 120*60*1000);
+        ix = mainindex;
+        for(i=0; insects; i++){
+                ix->sects[i]->writechan = chancreate(sizeof(ulong), 1);
+                ix->sects[i]->writedonechan = chancreate(sizeof(ulong), 1);
+                vtproc(icachewriteproc, ix->sects[i]);
+        }
+        vtproc(icachewritecoord, nil);
+        vtproc(delaykickroundproc, &iwrite.round);
+}
+
+static IEntry*
+nextchunk(Index *ix, ISect *is, IEntry **pie, u64int *paddr, uint *pnbuf)
+{
+        u64int addr, naddr;
+        uint nbuf;
+        int bsize;
+        IEntry *iefirst, *ie, **l;
+
+        bsize = 1<blocklog;
+        iefirst = *pie;
+        addr = is->blockbase + ((u64int)(hashbits(iefirst->score, 32) / ix->div - is->start) << is->blocklog);
+        nbuf = 0;
+        for(l=&iefirst->nextdirty; (ie=*l)!=nil; l=&(*l)->nextdirty){
+                naddr = is->blockbase + ((u64int)(hashbits(ie->score, 32) / ix->div - is->start) << is->blocklog);
+                if(naddr - addr >= Bufsize)
+                        break;
+                nbuf = naddr-addr;
+        }
+        nbuf += bsize;
+
+        *l = nil;
+        *pie = ie;
+        *paddr = addr;
+        *pnbuf = nbuf;
+        return iefirst;
+}
+        
+static int
+icachewritesect(Index *ix, ISect *is, u8int *buf)
+{
+        int err, h, bsize;
+        u32int lo, hi;
+        u64int addr, naddr;
+        uint nbuf, off;
+        DBlock *b;
+        IBucket ib;
+        IEntry *ie, *iedirty, **l, *chunk;
+
+        lo = is->start * ix->div;
+        if(TWID32/ix->div < is->stop)
+                hi = TWID32;
+        else
+                hi = is->stop * ix->div - 1;
+
+        trace(TraceProc, "icachewritesect enter %ud %ud %llud", lo, hi, iwrite.as.aa);
+
+        iedirty = icachedirty(lo, hi, iwrite.as.aa);
+        iedirty = iesort(iedirty);
+        bsize = 1<blocklog;
+        err = 0;
+
+        while(iedirty){
+                sleep(icachesleeptime);
+                trace(TraceProc, "icachewritesect nextchunk");
+                chunk = nextchunk(ix, is, &iedirty, &addr, &nbuf);
+
+                trace(TraceProc, "icachewritesect readpart 0x%llux+0x%ux", addr, nbuf);
+                if(readpart(is->part, addr, buf, nbuf) < 0){
+                        // XXX
+                        fprint(2, "icachewriteproc readpart: %r\n");
+                        err  = -1;
+                        continue;
+                }
+                trace(TraceProc, "icachewritesect updatebuf");
+                addstat(StatIsectReadBytes, nbuf);
+                addstat(StatIsectRead, 1);
+
+                for(l=&chunk; (ie=*l)!=nil; l=&ie->nextdirty){
+                again:
+                        naddr = is->blockbase + ((u64int)(hashbits(ie->score, 32) / ix->div - is->start) << is->blocklog);
+                        off = naddr - addr;
+                        if(off+bsize > nbuf){
+                                fprint(2, "whoops! addr=0x%llux nbuf=%ud addr+nbuf=0x%llux naddr=0x%llux\n",
+                                        addr, nbuf, addr+nbuf, naddr);
+                                assert(off+bsize <= nbuf);
+                        }
+                        unpackibucket(&ib, buf+off, is->bucketmagic);
+                        if(okibucket(&ib, is) < 0){
+                                fprint(2, "bad bucket XXX\n");
+                                goto skipit;
+                        }
+                        trace(TraceProc, "icachewritesect add %V at 0x%llux", ie->score, naddr);
+                        h = bucklook(ie->score, ie->ia.type, ib.data, ib.n);
+                        if(h & 1){
+                                h ^= 1;
+                                packientry(ie, &ib.data[h]);
+                        }else if(ib.n < is->buckmax){
+                                memmove(&ib.data[h+IEntrySize], &ib.data[h], ib.n*IEntrySize - h);
+                                ib.n++;
+                                packientry(ie, &ib.data[h]);
+                        }else{
+                                fprint(2, "bucket overflow XXX\n");
+                        skipit:
+                                err = -1;
+                                *l = ie->nextdirty;
+                                ie = *l;
+                                if(ie)
+                                        goto again;
+                                else
+                                        break;
+                        }
+                        packibucket(&ib, buf+off, is->bucketmagic);
+                        if((b = _getdblock(is->part, naddr, ORDWR, 0)) != nil){
+                                memmove(b->data, buf+off, bsize);
+                                putdblock(b);
+                        }
+                }
+
+                trace(TraceProc, "icachewritesect writepart", addr, nbuf);
+                if(writepart(is->part, addr, buf, nbuf) < 0){
+                        // XXX
+                        fprint(2, "icachewriteproc writepart: %r\n");
+                        err = -1;
+                        continue;
+                }
+                addstat(StatIsectWriteBytes, nbuf);
+                addstat(StatIsectWrite, 1);
+                icacheclean(chunk);
+        }
+
+        trace(TraceProc, "icachewritesect done");
+        return err;
+}
+
+static void
+icachewriteproc(void *v)
+{
+        uint bsize;
+        ISect *is;
+        Index *ix;
+        u8int *buf;
+
+        ix = mainindex;
+        is = v;
+        threadsetname("icachewriteproc:%s", is->part->name);
+
+        bsize = 1<blocklog;
+        buf = emalloc(Bufsize+bsize);
+        buf = (u8int*)(((ulong)buf+bsize-1)&~(ulong)(bsize-1));
+
+        for(;;){
+                trace(TraceProc, "icachewriteproc recv");
+                recv(is->writechan, 0);
+                trace(TraceWork, "start");
+                icachewritesect(ix, is, buf);
+                trace(TraceProc, "icachewriteproc send");
+                trace(TraceWork, "finish");
+                send(is->writedonechan, 0);
+        }
+}
+
+static void
+icachewritecoord(void *v)
+{
+        int i;
+        Index *ix;
+        AState as;
+
+        USED(v);
+
+        threadsetname("icachewritecoord");
+
+        ix = mainindex;
+        iwrite.as = diskstate();
+
+        for(;;){
+                trace(TraceProc, "icachewritecoord sleep");
+                waitforkick(&iwrite.round);
+                trace(TraceWork, "start");
+                as = diskstate();
+                if(as.arena==iwrite.as.arena && as.aa==iwrite.as.aa){
+                        /* will not be able to do anything more than last flush - kick disk */
+                        trace(TraceProc, "icachewritecoord flush dcache");
+                        kickdcache();
+                        trace(TraceProc, "icachewritecoord flushed dcache");
+                }
+                iwrite.as = as;
+
+                trace(TraceProc, "icachewritecoord start flush");
+                if(iwrite.as.arena){
+                        for(i=0; insects; i++)
+                                send(ix->sects[i]->writechan, 0);
+                        if(ix->bloom)
+                                send(ix->bloom->writechan, 0);
+                
+                        for(i=0; insects; i++)
+                                recv(ix->sects[i]->writedonechan, 0);
+                        if(ix->bloom)
+                                recv(ix->bloom->writedonechan, 0);
+
+                        trace(TraceProc, "icachewritecoord donewrite");
+                        setatailstate(&iwrite.as);
+                }
+                icacheclean(nil);        /* wake up anyone waiting */
+                trace(TraceWork, "finish");
+                addstat(StatIcacheFlush, 1);
+        }
+}
+
+void
+flushicache(void)
+{
+        trace(TraceProc, "flushicache enter");
+        kickround(&iwrite.round, 1);
+        trace(TraceProc, "flushicache exit");
+}
+
+void
+kickicache(void)
+{
+        kickround(&iwrite.round, 0);
+}
+
+void
+delaykickicache(void)
+{
+        delaykickround(&iwrite.round);
+}
+
+static IEntry*
+iesort(IEntry *ie)
+{
+        int cmp;
+        IEntry **l;
+        IEntry *ie1, *ie2, *sorted;
+
+        if(ie == nil || ie->nextdirty == nil)
+                return ie;
+
+        /* split the lists */
+        ie1 = ie;
+        ie2 = ie;
+        if(ie2)
+                ie2 = ie2->nextdirty;
+        if(ie2)
+                ie2 = ie2->nextdirty;
+        while(ie1 && ie2){
+                ie1 = ie1->nextdirty;
+                ie2 = ie2->nextdirty;
+                if(ie2)
+                        ie2 = ie2->nextdirty;
+        }
+        if(ie1){
+                ie2 = ie1->nextdirty;
+                ie1->nextdirty = nil;
+        }
+
+        /* sort the lists */
+        ie1 = iesort(ie);
+        ie2 = iesort(ie2);
+
+        /* merge the lists */
+        sorted = nil;
+        l = &sorted;
+        cmp = 0;
+        while(ie1 || ie2){
+                if(ie1 && ie2)
+                        cmp = scorecmp(ie1->score, ie2->score);
+                if(ie1==nil || (ie2 && cmp > 0)){
+                        *l = ie2;
+                        l = &ie2->nextdirty;
+                        ie2 = ie2->nextdirty;
+                }else{
+                        *l = ie1;
+                        l = &ie1->nextdirty;
+                        ie1 = ie1->nextdirty;
+                }
+        }
+        *l = nil;
+        return sorted;
+}
+
diff --git a/src/cmd/venti/srv/ifile.c b/src/cmd/venti/srv/ifile.c
t@@ -0,0 +1,93 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+int
+readifile(IFile *f, char *name)
+{
+        ZBlock *b;
+
+        b = readfile(name);
+        if(b == nil)
+                return -1;
+        f->name = name;
+        f->b = b;
+        f->pos = 0;
+        return 0;
+}
+
+void
+freeifile(IFile *f)
+{
+        freezblock(f->b);
+        f->b = nil;
+        f->pos = 0;
+}
+
+int
+partifile(IFile *f, Part *part, u64int start, u32int size)
+{
+        ZBlock *b;
+
+        b = alloczblock(size, 0, part->blocksize);
+        if(b == nil)
+                return -1;
+        if(readpart(part, start, b->data, size) < 0){
+                seterr(EAdmin, "can't read %s: %r", part->name);
+                freezblock(b);
+                return -1;
+        }
+        f->name = part->name;
+        f->b = b;
+        f->pos = 0;
+        return 0;
+}
+
+/*
+ * return the next non-blank input line,
+ * stripped of leading white space and with # comments eliminated
+ */
+char*
+ifileline(IFile *f)
+{
+        char *s, *e, *t;
+        int c;
+
+        for(;;){
+                s = (char*)&f->b->data[f->pos];
+                e = memchr(s, '\n', f->b->len - f->pos);
+                if(e == nil)
+                        return nil;
+                *e++ = '\0';
+                f->pos = e - (char*)f->b->data;
+                t = strchr(s, '#');
+                if(t != nil)
+                        *t = '\0';
+                for(; c = *s; s++)
+                        if(c != ' ' && c != '\t' && c != '\r')
+                                return s;
+        }
+}
+
+int
+ifilename(IFile *f, char *dst)
+{
+        char *s;
+
+        s = ifileline(f);
+        if(s == nil || strlen(s) >= ANameSize)
+                return -1;
+        namecp(dst, s);
+        return 0;
+}
+
+int
+ifileu32int(IFile *f, u32int *r)
+{
+        char *s;
+
+        s = ifileline(f);
+        if(s == nil)
+                return -1;
+        return stru32int(s, r);
+}
diff --git a/src/cmd/venti/srv/index.c b/src/cmd/venti/srv/index.c
t@@ -0,0 +1,819 @@
+/*
+ * Index, mapping scores to log positions. 
+ *
+ * The index is made up of some number of index sections, each of
+ * which is typically stored on a different disk.  The blocks in all the 
+ * index sections are logically numbered, with each index section 
+ * responsible for a range of blocks.  Blocks are typically 8kB.
+ *
+ * The N index blocks are treated as a giant hash table.  The top 32 bits
+ * of score are used as the key for a lookup.  Each index block holds
+ * one hash bucket, which is responsible for ceil(2^32 / N) of the key space.
+ * 
+ * The index is sized so that a particular bucket is extraordinarily 
+ * unlikely to overflow: assuming compressed data blocks are 4kB 
+ * on disk, and assuming each block has a 40 byte index entry,
+ * the index data will be 1% of the total data.  Since scores are essentially
+ * random, all buckets should be about the same fullness.
+ * A factor of 5 gives us a wide comfort boundary to account for 
+ * random variation.  So the index disk space should be 5% of the arena disk space.
+ */
+
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+//static int        bucklook(u8int *score, int type, u8int *data, int n);
+//static int        writebucket(ISect *is, u32int buck, IBucket *ib, DBlock *b);
+//static int        okibucket(IBucket *ib, ISect *is);
+static int        initindex1(Index*);
+static ISect        *initisect1(ISect *is);
+//static int        splitiblock(Index *ix, DBlock *b, ISect *is, u32int buck, IBucket *ib);
+
+#define KEY(k,d)        ((d) ? (k)>>(32-(d)) : 0)
+
+//static QLock        indexlock;        //ZZZ
+
+static char IndexMagic[] = "venti index configuration";
+
+Index*
+initindex(char *name, ISect **sects, int n)
+{
+        IFile f;
+        Index *ix;
+        ISect *is;
+        u32int last, blocksize, tabsize;
+        int i;
+
+        if(n <= 0){
+fprint(2, "bad n\n");
+                seterr(EOk, "no index sections to initialize index");
+                return nil;
+        }
+        ix = MKZ(Index);
+        if(ix == nil){
+fprint(2, "no mem\n");
+                seterr(EOk, "can't initialize index: out of memory");
+                freeindex(ix);
+                return nil;
+        }
+
+        tabsize = sects[0]->tabsize;
+        if(partifile(&f, sects[0]->part, sects[0]->tabbase, tabsize) < 0)
+                return nil;
+        if(parseindex(&f, ix) < 0){
+                freeifile(&f);
+                freeindex(ix);
+                return nil;
+        }
+        freeifile(&f);
+        if(namecmp(ix->name, name) != 0){
+                seterr(ECorrupt, "mismatched index name: found %s expected %s", ix->name, name);
+                return nil;
+        }
+        if(ix->nsects != n){
+                seterr(ECorrupt, "mismatched number index sections: found %d expected %d", n, ix->nsects);
+                freeindex(ix);
+                return nil;
+        }
+        ix->sects = sects;
+        last = 0;
+        blocksize = ix->blocksize;
+        for(i = 0; i < ix->nsects; i++){
+                is = sects[i];
+                if(namecmp(ix->name, is->index) != 0
+                || is->blocksize != blocksize
+                || is->tabsize != tabsize
+                || namecmp(is->name, ix->smap[i].name) != 0
+                || is->start != ix->smap[i].start
+                || is->stop != ix->smap[i].stop
+                || last != is->start
+                || is->start > is->stop){
+                        seterr(ECorrupt, "inconsistent index sections in %s", ix->name);
+                        freeindex(ix);
+                        return nil;
+                }
+                last = is->stop;
+        }
+        ix->tabsize = tabsize;
+        ix->buckets = last;
+
+        if(initindex1(ix) < 0){
+                freeindex(ix);
+                return nil;
+        }
+
+        ix->arenas = MKNZ(Arena*, ix->narenas);
+        if(maparenas(ix->amap, ix->arenas, ix->narenas, ix->name) < 0){
+                freeindex(ix);
+                return nil;
+        }
+
+        return ix;
+}
+
+static int
+initindex1(Index *ix)
+{
+        u32int buckets;
+
+        ix->div = (((u64int)1 << 32) + ix->buckets - 1) / ix->buckets;
+        buckets = (((u64int)1 << 32) - 1) / ix->div + 1;
+        if(buckets != ix->buckets){
+                seterr(ECorrupt, "inconsistent math for divisor and buckets in %s", ix->name);
+                return -1;
+        }
+
+        return 0;
+}
+
+int
+wbindex(Index *ix)
+{
+        Fmt f;
+        ZBlock *b;
+        int i;
+
+        if(ix->nsects == 0){
+                seterr(EOk, "no sections in index %s", ix->name);
+                return -1;
+        }
+        b = alloczblock(ix->tabsize, 1, ix->blocksize);
+        if(b == nil){
+                seterr(EOk, "can't write index configuration: out of memory");
+                return -1;
+        }
+        fmtzbinit(&f, b);
+        if(outputindex(&f, ix) < 0){
+                seterr(EOk, "can't make index configuration: table storage too small %d", ix->tabsize);
+                freezblock(b);
+                return -1;
+        }
+        for(i = 0; i < ix->nsects; i++){
+                if(writepart(ix->sects[i]->part, ix->sects[i]->tabbase, b->data, ix->tabsize) < 0){
+                        seterr(EOk, "can't write index: %r");
+                        freezblock(b);
+                        return -1;
+                }
+        }
+        freezblock(b);
+
+        for(i = 0; i < ix->nsects; i++)
+                if(wbisect(ix->sects[i]) < 0)
+                        return -1;
+
+        return 0;
+}
+
+/*
+ * index: IndexMagic '\n' version '\n' name '\n' blocksize '\n' [V2: bitblocks '\n'] sections arenas
+ * version, blocksize: u32int
+ * name: max. ANameSize string
+ * sections, arenas: AMap
+ */
+int
+outputindex(Fmt *f, Index *ix)
+{
+        if(fmtprint(f, "%s\n%ud\n%s\n%ud\n", IndexMagic, ix->version, ix->name, ix->blocksize) < 0
+        || outputamap(f, ix->smap, ix->nsects) < 0
+        || outputamap(f, ix->amap, ix->narenas) < 0)
+                return -1;
+        return 0;
+}
+
+int
+parseindex(IFile *f, Index *ix)
+{
+        AMapN amn;
+        u32int v;
+        char *s;
+
+        /*
+         * magic
+         */
+        s = ifileline(f);
+        if(s == nil || strcmp(s, IndexMagic) != 0){
+                seterr(ECorrupt, "bad index magic for %s", f->name);
+                return -1;
+        }
+
+        /*
+         * version
+         */
+        if(ifileu32int(f, &v) < 0){
+                seterr(ECorrupt, "syntax error: bad version number in %s", f->name);
+                return -1;
+        }
+        ix->version = v;
+        if(ix->version != IndexVersion){
+                seterr(ECorrupt, "bad version number in %s", f->name);
+                return -1;
+        }
+
+        /*
+         * name
+         */
+        if(ifilename(f, ix->name) < 0){
+                seterr(ECorrupt, "syntax error: bad index name in %s", f->name);
+                return -1;
+        }
+
+        /*
+         * block size
+         */
+        if(ifileu32int(f, &v) < 0){
+                seterr(ECorrupt, "syntax error: bad block size number in %s", f->name);
+                return -1;
+        }
+        ix->blocksize = v;
+
+        if(parseamap(f, &amn) < 0)
+                return -1;
+        ix->nsects = amn.n;
+        ix->smap = amn.map;
+
+        if(parseamap(f, &amn) < 0)
+                return -1;
+        ix->narenas = amn.n;
+        ix->amap = amn.map;
+
+        return 0;
+}
+
+/*
+ * initialize an entirely new index
+ */
+Index *
+newindex(char *name, ISect **sects, int n)
+{
+        Index *ix;
+        AMap *smap;
+        u64int nb;
+        u32int div, ub, xb, fb, start, stop, blocksize, tabsize;
+        int i, j;
+
+        if(n < 1){
+                seterr(EOk, "creating index with no index sections");
+                return nil;
+        }
+
+        /*
+         * compute the total buckets available in the index,
+         * and the total buckets which are used.
+         */
+        nb = 0;
+        blocksize = sects[0]->blocksize;
+        tabsize = sects[0]->tabsize;
+        for(i = 0; i < n; i++){
+                if(sects[i]->start != 0 || sects[i]->stop != 0
+                || sects[i]->index[0] != '\0'){
+                        seterr(EOk, "creating new index using non-empty section %s", sects[i]->name);
+                        return nil;
+                }
+                if(blocksize != sects[i]->blocksize){
+                        seterr(EOk, "mismatched block sizes in index sections");
+                        return nil;
+                }
+                if(tabsize != sects[i]->tabsize){
+                        seterr(EOk, "mismatched config table sizes in index sections");
+                        return nil;
+                }
+                nb += sects[i]->blocks;
+        }
+
+        /*
+         * check for duplicate names
+         */
+        for(i = 0; i < n; i++){
+                for(j = i + 1; j < n; j++){
+                        if(namecmp(sects[i]->name, sects[j]->name) == 0){
+                                seterr(EOk, "duplicate section name %s for index %s", sects[i]->name, name);
+                                return nil;
+                        }
+                }
+        }
+
+        if(nb >= ((u64int)1 << 32)){
+                seterr(EBug, "index too large");
+                return nil;
+        }
+
+        fb = 0;
+        div = (((u64int)1 << 32) + nb - 1) / nb;
+        ub = (((u64int)1 << 32) - 1) / div + 1;
+        if(div < 100){
+                seterr(EBug, "index divisor too coarse");
+                return nil;
+        }
+        if(ub > nb){
+                seterr(EBug, "index initialization math wrong");
+                return nil;
+        }
+        xb = nb - ub;
+
+        /*
+         * initialize each of the index sections
+         * and the section map table
+         */
+        smap = MKNZ(AMap, n);
+        if(smap == nil){
+                seterr(EOk, "can't create new index: out of memory");
+                return nil;
+        }
+        start = 0;
+        for(i = 0; i < n; i++){
+                stop = start + sects[i]->blocks - xb / n;
+                if(i == n - 1)
+                        stop = ub;
+                sects[i]->start = start;
+                sects[i]->stop = stop;
+                namecp(sects[i]->index, name);
+
+                smap[i].start = start;
+                smap[i].stop = stop;
+                namecp(smap[i].name, sects[i]->name);
+                start = stop;
+        }
+
+        /*
+         * initialize the index itself
+         */
+        ix = MKZ(Index);
+        if(ix == nil){
+                seterr(EOk, "can't create new index: out of memory");
+                free(smap);
+                return nil;
+        }
+        ix->version = IndexVersion;
+        namecp(ix->name, name);
+        ix->sects = sects;
+        ix->smap = smap;
+        ix->nsects = n;
+        ix->blocksize = blocksize;
+        ix->buckets = ub;
+        ix->tabsize = tabsize;
+        ix->div = div;
+        ix->bitblocks = fb;
+
+        if(initindex1(ix) < 0){
+                free(smap);
+                return nil;
+        }
+
+        return ix;
+}
+
+ISect*
+initisect(Part *part)
+{
+        ISect *is;
+        ZBlock *b;
+        int ok;
+
+        b = alloczblock(HeadSize, 0, 0);
+        if(b == nil || readpart(part, PartBlank, b->data, HeadSize) < 0){
+                seterr(EAdmin, "can't read index section header: %r");
+                return nil;
+        }
+
+        is = MKZ(ISect);
+        if(is == nil){
+                freezblock(b);
+                return nil;
+        }
+        is->part = part;
+        ok = unpackisect(is, b->data);
+        freezblock(b);
+        if(ok < 0){
+                seterr(ECorrupt, "corrupted index section header: %r");
+                freeisect(is);
+                return nil;
+        }
+
+        if(is->version != ISectVersion1 && is->version != ISectVersion2){
+                seterr(EAdmin, "unknown index section version %d", is->version);
+                freeisect(is);
+                return nil;
+        }
+
+        return initisect1(is);
+}
+
+ISect*
+newisect(Part *part, u32int vers, char *name, u32int blocksize, u32int tabsize)
+{
+        ISect *is;
+        u32int tabbase;
+
+        is = MKZ(ISect);
+        if(is == nil)
+                return nil;
+
+        namecp(is->name, name);
+        is->version = vers;
+        is->part = part;
+        is->blocksize = blocksize;
+        is->start = 0;
+        is->stop = 0;
+        tabbase = (PartBlank + HeadSize + blocksize - 1) & ~(blocksize - 1);
+        is->blockbase = (tabbase + tabsize + blocksize - 1) & ~(blocksize - 1);
+        is->blocks = is->part->size / blocksize - is->blockbase / blocksize;
+        is->bucketmagic = 0;
+        if(is->version == ISectVersion2){
+                do{
+                        is->bucketmagic = fastrand();
+                }while(is->bucketmagic==0);
+        }
+        is = initisect1(is);
+        if(is == nil)
+                return nil;
+
+        return is;
+}
+
+/*
+ * initialize the computed parameters for an index
+ */
+static ISect*
+initisect1(ISect *is)
+{
+        u64int v;
+
+        is->buckmax = (is->blocksize - IBucketSize) / IEntrySize;
+        is->blocklog = u64log2(is->blocksize);
+        if(is->blocksize != (1 << is->blocklog)){
+                seterr(ECorrupt, "illegal non-power-of-2 bucket size %d\n", is->blocksize);
+                freeisect(is);
+                return nil;
+        }
+        partblocksize(is->part, is->blocksize);
+        is->tabbase = (PartBlank + HeadSize + is->blocksize - 1) & ~(is->blocksize - 1);
+        if(is->tabbase >= is->blockbase){
+                seterr(ECorrupt, "index section config table overlaps bucket storage");
+                freeisect(is);
+                return nil;
+        }
+        is->tabsize = is->blockbase - is->tabbase;
+        v = is->part->size & ~(u64int)(is->blocksize - 1);
+        if(is->blockbase + (u64int)is->blocks * is->blocksize != v){
+                seterr(ECorrupt, "invalid blocks in index section %s", is->name);
+//ZZZZZZZZZ
+//                freeisect(is);
+//                return nil;
+        }
+
+        if(is->stop - is->start > is->blocks){
+                seterr(ECorrupt, "index section overflows available space");
+                freeisect(is);
+                return nil;
+        }
+        if(is->start > is->stop){
+                seterr(ECorrupt, "invalid index section range");
+                freeisect(is);
+                return nil;
+        }
+
+        return is;
+}
+
+int
+wbisect(ISect *is)
+{
+        ZBlock *b;
+
+        b = alloczblock(HeadSize, 1, 0);
+        if(b == nil)
+//ZZZ set error?
+                return -1;
+
+        if(packisect(is, b->data) < 0){
+                seterr(ECorrupt, "can't make index section header: %r");
+                freezblock(b);
+                return -1;
+        }
+        if(writepart(is->part, PartBlank, b->data, HeadSize) < 0){
+                seterr(EAdmin, "can't write index section header: %r");
+                freezblock(b);
+                return -1;
+        }
+        freezblock(b);
+
+        return 0;
+}
+
+void
+freeisect(ISect *is)
+{
+        if(is == nil)
+                return;
+        free(is);
+}
+
+void
+freeindex(Index *ix)
+{
+        int i;
+
+        if(ix == nil)
+                return;
+        free(ix->amap);
+        free(ix->arenas);
+        if(ix->sects)
+                for(i = 0; i < ix->nsects; i++)
+                        freeisect(ix->sects[i]);
+        free(ix->sects);
+        free(ix->smap);
+        free(ix);
+}
+
+/*
+ * write a clump to an available arena in the index
+ * and return the address of the clump within the index.
+ZZZ question: should this distinguish between an arena
+filling up and real errors writing the clump?
+ */
+u64int
+writeiclump(Index *ix, Clump *c, u8int *clbuf, u64int *pa)
+{
+        u64int a;
+        int i;
+
+        trace(TraceLump, "writeiclump enter");
+        for(i = ix->mapalloc; i < ix->narenas; i++){
+                a = writeaclump(ix->arenas[i], c, clbuf, ix->amap[i].start, pa);
+                if(a != TWID64){
+                        ix->mapalloc = i;        /* assuming write is atomic, race is okay */
+                        trace(TraceLump, "writeiclump exit");
+                        return a;
+                }
+        }
+
+        seterr(EAdmin, "no space left in arenas");
+        trace(TraceLump, "writeiclump failed");
+        return TWID64;
+}
+
+/*
+ * convert an arena index to an relative arena address
+ */
+Arena*
+amapitoa(Index *ix, u64int a, u64int *aa)
+{
+        int i, r, l, m;
+
+        l = 1;
+        r = ix->narenas - 1;
+        while(l <= r){
+                m = (r + l) / 2;
+                if(ix->amap[m].start <= a)
+                        l = m + 1;
+                else
+                        r = m - 1;
+        }
+        l--;
+
+        if(a > ix->amap[l].stop){
+for(i=0; inarenas; i++)
+        print("arena %d: %llux - %llux\n", i, ix->amap[i].start, ix->amap[i].stop);
+print("want arena %d for %llux\n", l, a);
+                seterr(ECrash, "unmapped address passed to amapitoa");
+                return nil;
+        }
+
+        if(ix->arenas[l] == nil){
+                seterr(ECrash, "unmapped arena selected in amapitoa");
+                return nil;
+        }
+        *aa = a - ix->amap[l].start;
+        return ix->arenas[l];
+}
+
+int
+iaddrcmp(IAddr *ia1, IAddr *ia2)
+{
+        return ia1->type != ia2->type
+                || ia1->size != ia2->size
+                || ia1->blocks != ia2->blocks
+                || ia1->addr != ia2->addr;
+}
+
+/*
+ * lookup the score in the partition
+ *
+ * nothing needs to be explicitly locked:
+ * only static parts of ix are used, and
+ * the bucket is locked by the DBlock lock.
+ */
+int
+loadientry(Index *ix, u8int *score, int type, IEntry *ie)
+{
+        ISect *is;
+        DBlock *b;
+        IBucket ib;
+        u32int buck;
+        int h, ok;
+
+        ok = -1;
+
+        trace(TraceLump, "loadientry enter");
+
+        /*
+        qlock(&stats.lock);
+        stats.indexreads++;
+        qunlock(&stats.lock);
+        */
+
+        if(!inbloomfilter(mainindex->bloom, score)){
+                trace(TraceLump, "loadientry bloomhit");
+                return -1;
+        }
+
+        trace(TraceLump, "loadientry loadibucket");
+        b = loadibucket(ix, score, &is, &buck, &ib);
+        trace(TraceLump, "loadientry loadedibucket");
+        if(b == nil)
+                return -1;
+
+        if(okibucket(&ib, is) < 0){
+                trace(TraceLump, "loadientry badbucket");
+                goto out;
+        }
+
+        h = bucklook(score, type, ib.data, ib.n);
+        if(h & 1){
+                h ^= 1;
+                trace(TraceLump, "loadientry found");
+                unpackientry(ie, &ib.data[h]);
+                ok = 0;
+                goto out;
+        }
+        trace(TraceLump, "loadientry notfound");
+        addstat(StatBloomFalseMiss, 1);
+out:
+        putdblock(b);
+        trace(TraceLump, "loadientry exit");
+        return ok;
+}
+
+int
+okibucket(IBucket *ib, ISect *is)
+{
+        if(ib->n <= is->buckmax)
+                return 0;
+
+        seterr(EICorrupt, "corrupted disk index bucket: n=%ud max=%ud, range=[%lud,%lud)",
+                ib->n, is->buckmax, is->start, is->stop);
+        return -1;
+}
+
+/*
+ * look for score within data;
+ * return 1 | byte index of matching index,
+ * or 0 | index of least element > score
+ */
+int
+bucklook(u8int *score, int otype, u8int *data, int n)
+{
+        int i, r, l, m, h, c, cc, type;
+
+        type = vttodisktype(otype);
+        l = 0;
+        r = n - 1;
+        while(l <= r){
+                m = (r + l) >> 1;
+                h = m * IEntrySize;
+                for(i = 0; i < VtScoreSize; i++){
+                        c = score[i];
+                        cc = data[h + i];
+                        if(c != cc){
+                                if(c > cc)
+                                        l = m + 1;
+                                else
+                                        r = m - 1;
+                                goto cont;
+                        }
+                }
+                cc = data[h + IEntryTypeOff];
+                if(type != cc){
+                        if(type > cc)
+                                l = m + 1;
+                        else
+                                r = m - 1;
+                        goto cont;
+                }
+                return h | 1;
+        cont:;
+        }
+
+        return l * IEntrySize;
+}
+
+/*
+ * compare two IEntries; consistent with bucklook
+ */
+int
+ientrycmp(const void *vie1, const void *vie2)
+{
+        u8int *ie1, *ie2;
+        int i, v1, v2;
+
+        ie1 = (u8int*)vie1;
+        ie2 = (u8int*)vie2;
+        for(i = 0; i < VtScoreSize; i++){
+                v1 = ie1[i];
+                v2 = ie2[i];
+                if(v1 != v2){
+                        if(v1 < v2)
+                                return -1;
+                        return 1;
+                }
+        }
+        v1 = ie1[IEntryTypeOff];
+        v2 = ie2[IEntryTypeOff];
+        if(v1 != v2){
+                if(v1 < v2)
+                        return -1;
+                return 1;
+        }
+        return 0;
+}
+
+/*
+ * find the number of the index section holding bucket #buck
+ */
+int
+indexsect0(Index *ix, u32int buck)
+{
+        int r, l, m;
+
+        l = 1;
+        r = ix->nsects - 1;
+        while(l <= r){
+                m = (r + l) >> 1;
+                if(ix->sects[m]->start <= buck)
+                        l = m + 1;
+                else
+                        r = m - 1;
+        }
+        return l - 1;
+}
+
+/*
+ * load the index block at bucket #buck
+ */
+static DBlock*
+loadibucket0(Index *ix, u32int buck, ISect **pis, u32int *pbuck, IBucket *ib, int mode)
+{
+        ISect *is;
+        DBlock *b;
+
+        is = ix->sects[indexsect0(ix, buck)];
+        if(buck < is->start || is->stop <= buck){
+                seterr(EAdmin, "index lookup out of range: %ud not found in index\n", buck);
+                return nil;
+        }
+
+        buck -= is->start;
+        if((b = getdblock(is->part, is->blockbase + ((u64int)buck << is->blocklog), mode)) == nil)
+                return nil;
+
+        if(pis)
+                *pis = is;
+        if(pbuck)
+                *pbuck = buck;
+        if(ib)
+                unpackibucket(ib, b->data, is->bucketmagic);
+        return b;
+}
+
+/*
+ * find the number of the index section holding score
+ */
+static int
+indexsect1(Index *ix, u8int *score)
+{
+        return indexsect0(ix, hashbits(score, 32) / ix->div);
+}
+
+/*
+ * load the index block responsible for score.
+ */
+static DBlock*
+loadibucket1(Index *ix, u8int *score, ISect **pis, u32int *pbuck, IBucket *ib)
+{
+        return loadibucket0(ix, hashbits(score, 32)/ix->div, pis, pbuck, ib, OREAD);
+}
+
+int
+indexsect(Index *ix, u8int *score)
+{
+        return indexsect1(ix, score);
+}
+
+DBlock*
+loadibucket(Index *ix, u8int *score, ISect **pis, u32int *pbuck, IBucket *ib)
+{
+        return loadibucket1(ix, score, pis, pbuck, ib);
+}
+
+
diff --git a/src/cmd/venti/srv/lump.c b/src/cmd/venti/srv/lump.c
t@@ -0,0 +1,249 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+int                        queuewrites = 0;
+int                        writestodevnull = 0;
+
+static Packet                *readilump(Lump *u, IAddr *ia, u8int *score, int rac);
+
+Packet*
+readlump(u8int *score, int type, u32int size, int *cached)
+{
+        Lump *u;
+        Packet *p;
+        IAddr ia;
+        u32int n;
+        int rac;
+
+        trace(TraceLump, "readlump enter");
+/*
+        qlock(&stats.lock);
+        stats.lumpreads++;
+        qunlock(&stats.lock);
+*/
+        if(scorecmp(score, zeroscore) == 0)
+                return packetalloc();
+        u = lookuplump(score, type);
+        if(u->data != nil){
+                trace(TraceLump, "readlump lookuplump hit");
+                if(cached)
+                        *cached = 1;
+                n = packetsize(u->data);
+                if(n > size){
+                        seterr(EOk, "read too small: asked for %d need at least %d", size, n);
+                        putlump(u);
+
+                        return nil;
+                }
+                p = packetdup(u->data, 0, n);
+                putlump(u);
+                return p;
+        }
+
+        if(cached)
+                *cached = 0;
+
+        if(lookupscore(score, type, &ia, &rac) < 0){
+                //ZZZ place to check for someone trying to guess scores
+                seterr(EOk, "no block with score %V/%d exists", score, type);
+
+                putlump(u);
+                return nil;
+        }
+        if(ia.size > size){
+                seterr(EOk, "read too small 1: asked for %d need at least %d", size, ia.size);
+
+                putlump(u);
+                return nil;
+        }
+
+        trace(TraceLump, "readlump readilump");
+        p = readilump(u, &ia, score, rac);
+        putlump(u);
+
+        trace(TraceLump, "readlump exit");
+        return p;
+}
+
+/*
+ * save away a lump, and return it's score.
+ * doesn't store duplicates, but checks that the data is really the same.
+ */
+int
+writelump(Packet *p, u8int *score, int type, u32int creator, uint ms)
+{
+        Lump *u;
+        int ok;
+
+/*
+        qlock(&stats.lock);
+        stats.lumpwrites++;
+        qunlock(&stats.lock);
+*/
+
+        packetsha1(p, score);
+        if(packetsize(p) == 0 || writestodevnull==1){
+                packetfree(p);
+                return 0;
+        }
+
+        u = lookuplump(score, type);
+        if(u->data != nil){
+                ok = 0;
+                if(packetcmp(p, u->data) != 0){
+                        seterr(EStrange, "score collision");
+                        ok = -1;
+                }
+                packetfree(p);
+                putlump(u);
+                return ok;
+        }
+
+        if(writestodevnull==2){
+                packetfree(p);
+                return 0;
+        }
+
+        if(queuewrites)
+                return queuewrite(u, p, creator, ms);
+
+        ok = writeqlump(u, p, creator, ms);
+
+        putlump(u);
+        return ok;
+}
+
+int
+writeqlump(Lump *u, Packet *p, int creator, uint ms)
+{
+        ZBlock *flat;
+        Packet *old;
+        IAddr ia;
+        int ok;
+        int rac;
+
+        if(lookupscore(u->score, u->type, &ia, &rac) == 0){
+                /* assume the data is here! XXX */
+                packetfree(p);
+                ms = msec() - ms;
+                addstat2(StatRpcWriteOld, 1, StatRpcWriteOldTime, ms);
+                return 0;
+
+                /*
+                 * if the read fails,
+                 * assume it was corrupted data and store the block again
+                 */
+                old = readilump(u, &ia, u->score, rac);
+                if(old != nil){
+                        ok = 0;
+                        if(packetcmp(p, old) != 0){
+                                seterr(EStrange, "score collision");
+                                ok = -1;
+                        }
+                        packetfree(p);
+                        packetfree(old);
+
+                        ms = msec() - ms;
+                        addstat2(StatRpcWriteOld, 1, StatRpcWriteOldTime, ms);
+                        return ok;
+                }
+                logerr(EAdmin, "writelump: read %V failed, rewriting: %r\n", u->score);
+        }
+
+        flat = packet2zblock(p, packetsize(p));
+        ok = storeclump(mainindex, flat, u->score, u->type, creator, &ia);
+        freezblock(flat);
+        if(ok == 0)
+                ok = insertscore(u->score, &ia, 1);
+        if(ok == 0)
+                insertlump(u, p);
+        else
+                packetfree(p);
+
+        ms = msec() - ms;
+        addstat2(StatRpcWriteNew, 1, StatRpcWriteNewTime, ms);
+        return ok;
+}
+
+static void
+lreadahead(u64int a, Arena *arena, u64int aa, int n)
+{        
+        u8int buf[ClumpSize];
+        Clump cl;
+        IAddr ia;
+
+        while(n > 0) {
+                if (aa >= arena->memstats.used)
+                        break;
+                if(readarena(arena, aa, buf, ClumpSize) < ClumpSize)
+                        break;
+                if(unpackclump(&cl, buf, arena->clumpmagic) < 0)
+                        break;
+                ia.addr = a;
+                ia.type = cl.info.type;
+                ia.size = cl.info.uncsize;
+                ia.blocks = (cl.info.size + ClumpSize + (1 << ABlockLog) - 1) >> ABlockLog;
+                insertscore(cl.info.score, &ia, 0);
+                a += ClumpSize + cl.info.size;
+                aa += ClumpSize + cl.info.size;
+                n--;
+        }
+}
+
+static Packet*
+readilump(Lump *u, IAddr *ia, u8int *score, int rac)
+{
+        Arena *arena;
+        ZBlock *zb;
+        Packet *p, *pp;
+        Clump cl;
+        u64int a, aa;
+        u8int sc[VtScoreSize];
+
+        trace(TraceLump, "readilump enter");
+        arena = amapitoa(mainindex, ia->addr, &aa);
+        if(arena == nil){
+                trace(TraceLump, "readilump amapitoa failed");
+                return nil;
+        }
+
+        trace(TraceLump, "readilump loadclump");
+        zb = loadclump(arena, aa, ia->blocks, &cl, sc, paranoid);
+        if(zb == nil){
+                trace(TraceLump, "readilump loadclump failed");
+                return nil;
+        }
+
+        if(ia->size != cl.info.uncsize){
+                seterr(EInconsist, "index and clump size mismatch");
+                freezblock(zb);
+                return nil;
+        }
+        if(ia->type != cl.info.type){
+                seterr(EInconsist, "index and clump type mismatch");
+                freezblock(zb);
+                return nil;
+        }
+        if(scorecmp(score, sc) != 0){
+                seterr(ECrash, "score mismatch");
+                freezblock(zb);
+                return nil;
+        }
+
+        if(rac == 0) {
+                trace(TraceLump, "readilump readahead");
+                a = ia->addr + ClumpSize + cl.info.size;
+                aa += ClumpSize + cl.info.size;
+                lreadahead(a, arena, aa, 20);
+        }
+
+        trace(TraceLump, "readilump success");
+        p = zblock2packet(zb, cl.info.uncsize);
+        freezblock(zb);
+        pp = packetdup(p, 0, packetsize(p));
+        trace(TraceLump, "readilump insertlump");
+        insertlump(u, pp);
+        trace(TraceLump, "readilump exit");
+        return p;
+}
diff --git a/src/cmd/venti/srv/lumpcache.c b/src/cmd/venti/srv/lumpcache.c
t@@ -0,0 +1,417 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+/* #define CHECK(x)        x */
+#define CHECK(x)
+
+typedef struct LumpCache        LumpCache;
+
+enum
+{
+        HashLog                = 9,
+        HashSize        = 1<type = TWID8;
+                b->heap = TWID32;
+                b->next = last;
+                last = b;
+        }
+        lumpcache.free = last;
+        lumpcache.nheap = 0;
+}
+
+Lump*
+lookuplump(u8int *score, int type)
+{
+        uint ms;
+        Lump *b;
+        u32int h;
+
+        ms = msec();
+        trace(TraceLump, "lookuplump enter");
+        
+        h = hashbits(score, HashLog);
+
+        /*
+         * look for the block in the cache
+         */
+        qlock(&lumpcache.lock);
+        CHECK(checklumpcache());
+again:
+        for(b = lumpcache.heads[h]; b != nil; b = b->next){
+                if(scorecmp(score, b->score)==0 && type == b->type){
+                        addstat(StatLcacheHit, 1);
+                        trace(TraceLump, "lookuplump hit");
+                        goto found;
+                }
+        }
+
+        trace(TraceLump, "lookuplump miss");
+
+        /*
+         * missed: locate the block with the oldest second to last use.
+         * remove it from the heap, and fix up the heap.
+         */
+        while(lumpcache.free == nil){
+                trace(TraceLump, "lookuplump bump");
+                CHECK(checklumpcache());
+                if(bumplump() == nil){
+                        CHECK(checklumpcache());
+                        logerr(EAdmin, "all lump cache blocks in use");
+                        addstat(StatLcacheStall, 1);
+                        CHECK(checklumpcache());
+                        rsleep(&lumpcache.full);
+                        CHECK(checklumpcache());
+                        addstat(StatLcacheStall, -1);
+                        goto again;
+                }
+                CHECK(checklumpcache());
+        }
+
+        addstat(StatLcacheMiss, 1);
+        b = lumpcache.free;
+        lumpcache.free = b->next;
+
+        /*
+         * the new block has no last use, so assume it happens sometime in the middle
+ZZZ this is not reasonable
+         */
+        b->used = (b->used2 + lumpcache.now) / 2;
+
+        /*
+         * rechain the block on the correct hash chain
+         */
+        b->next = lumpcache.heads[h];
+        lumpcache.heads[h] = b;
+        if(b->next != nil)
+                b->next->prev = b;
+        b->prev = nil;
+
+        scorecp(b->score, score);
+        b->type = type;
+        b->size = 0;
+        b->data = nil;
+
+found:
+        b->ref++;
+        b->used2 = b->used;
+        b->used = lumpcache.now++;
+        if(b->heap != TWID32)
+                fixheap(b->heap, b);
+        CHECK(checklumpcache());
+        qunlock(&lumpcache.lock);
+
+
+        addstat(StatLumpStall, 1);
+        qlock(&b->lock);
+        addstat(StatLumpStall, -1);
+
+        trace(TraceLump, "lookuplump exit");
+        addstat2(StatLcacheRead, 1, StatLcacheReadTime, msec()-ms);
+        return b;
+}
+
+void
+insertlump(Lump *b, Packet *p)
+{
+        u32int size;
+
+        /*
+         * look for the block in the cache
+         */
+        trace(TraceLump, "insertlump enter");
+        qlock(&lumpcache.lock);
+        CHECK(checklumpcache());
+again:
+
+        addstat(StatLcacheWrite, 1);
+
+        /*
+         * missed: locate the block with the oldest second to last use.
+         * remove it from the heap, and fix up the heap.
+         */
+        size = packetasize(p);
+//ZZZ
+        while(lumpcache.avail < size){
+                trace(TraceLump, "insertlump bump");
+                CHECK(checklumpcache());
+                if(bumplump() == nil){
+                        logerr(EAdmin, "all lump cache blocks in use");
+                        addstat(StatLcacheStall, 1);
+                        CHECK(checklumpcache());
+                        rsleep(&lumpcache.full);
+                        CHECK(checklumpcache());
+                        addstat(StatLcacheStall, -1);
+                        goto again;
+                }
+                CHECK(checklumpcache());
+        }
+        b->data = p;
+        b->size = size;
+        lumpcache.avail -= size;
+        CHECK(checklumpcache());
+        qunlock(&lumpcache.lock);
+        trace(TraceLump, "insertlump exit");
+}
+
+void
+putlump(Lump *b)
+{
+        if(b == nil)
+                return;
+
+        trace(TraceLump, "putlump");
+        qunlock(&b->lock);
+        qlock(&lumpcache.lock);
+        CHECK(checklumpcache());
+        if(--b->ref == 0){
+                if(b->heap == TWID32)
+                        upheap(lumpcache.nheap++, b);
+                trace(TraceLump, "putlump wakeup");
+                rwakeupall(&lumpcache.full);
+        }
+        CHECK(checklumpcache());
+        qunlock(&lumpcache.lock);
+}
+
+/*
+ * remove some lump from use and update the free list and counters
+ */
+static Lump*
+bumplump(void)
+{
+        Lump *b;
+        u32int h;
+
+        /*
+         * remove blocks until we find one that is unused
+         * referenced blocks are left in the heap even though
+         * they can't be scavenged; this is simple a speed optimization
+         */
+        CHECK(checklumpcache());
+        for(;;){
+                if(lumpcache.nheap == 0){
+                        trace(TraceLump, "bumplump emptyheap");
+                        return nil;
+                }
+                b = lumpcache.heap[0];
+                delheap(b);
+                if(!b->ref){
+                        trace(TraceLump, "bumplump wakeup");
+                        rwakeupall(&lumpcache.full);
+                        break;
+                }
+        }
+
+        /*
+         * unchain the block
+         */
+        trace(TraceLump, "bumplump unchain");
+        if(b->prev == nil){
+                h = hashbits(b->score, HashLog);
+                if(lumpcache.heads[h] != b)
+                        sysfatal("bad hash chains in lump cache");
+                lumpcache.heads[h] = b->next;
+        }else
+                b->prev->next = b->next;
+        if(b->next != nil)
+                b->next->prev = b->prev;
+
+        if(b->data != nil){
+                packetfree(b->data);
+                b->data = nil;
+                lumpcache.avail += b->size;
+                b->size = 0;
+        }
+        b->type = TWID8;
+
+        b->next = lumpcache.free;
+        lumpcache.free = b;
+
+        CHECK(checklumpcache());
+        trace(TraceLump, "bumplump exit");
+        return b;
+}
+
+/*
+ * delete an arbitrary block from the heap
+ */
+static void
+delheap(Lump *db)
+{
+        fixheap(db->heap, lumpcache.heap[--lumpcache.nheap]);
+        db->heap = TWID32;
+}
+
+/*
+ * push an element up or down to it's correct new location
+ */
+static void
+fixheap(int i, Lump *b)
+{
+        if(upheap(i, b) == i)
+                downheap(i, b);
+}
+
+static int
+upheap(int i, Lump *b)
+{
+        Lump *bb;
+        u32int now;
+        int p;
+
+        now = lumpcache.now;
+        for(; i != 0; i = p){
+                p = (i - 1) >> 1;
+                bb = lumpcache.heap[p];
+                if(b->used2 - now >= bb->used2 - now)
+                        break;
+                lumpcache.heap[i] = bb;
+                bb->heap = i;
+        }
+
+        lumpcache.heap[i] = b;
+        b->heap = i;
+        return i;
+}
+
+static int
+downheap(int i, Lump *b)
+{
+        Lump *bb;
+        u32int now;
+        int k;
+
+        now = lumpcache.now;
+        for(; ; i = k){
+                k = (i << 1) + 1;
+                if(k >= lumpcache.nheap)
+                        break;
+                if(k + 1 < lumpcache.nheap && lumpcache.heap[k]->used2 - now > lumpcache.heap[k + 1]->used2 - now)
+                        k++;
+                bb = lumpcache.heap[k];
+                if(b->used2 - now <= bb->used2 - now)
+                        break;
+                lumpcache.heap[i] = bb;
+                bb->heap = i;
+        }
+
+        lumpcache.heap[i] = b;
+        b->heap = i;
+        return i;
+}
+
+static void
+findblock(Lump *bb)
+{
+        Lump *b, *last;
+        int h;
+
+        last = nil;
+        h = hashbits(bb->score, HashLog);
+        for(b = lumpcache.heads[h]; b != nil; b = b->next){
+                if(last != b->prev)
+                        sysfatal("bad prev link");
+                if(b == bb)
+                        return;
+                last = b;
+        }
+        sysfatal("block score=%V type=%#x missing from hash table", bb->score, bb->type);
+}
+
+void
+checklumpcache(void)
+{
+        Lump *b;
+        u32int size, now, nfree;
+        int i, k, refed;
+
+        now = lumpcache.now;
+        for(i = 0; i < lumpcache.nheap; i++){
+                if(lumpcache.heap[i]->heap != i)
+                        sysfatal("lc: mis-heaped at %d: %d", i, lumpcache.heap[i]->heap);
+                if(i > 0 && lumpcache.heap[(i - 1) >> 1]->used2 - now > lumpcache.heap[i]->used2 - now)
+                        sysfatal("lc: bad heap ordering");
+                k = (i << 1) + 1;
+                if(k < lumpcache.nheap && lumpcache.heap[i]->used2 - now > lumpcache.heap[k]->used2 - now)
+                        sysfatal("lc: bad heap ordering");
+                k++;
+                if(k < lumpcache.nheap && lumpcache.heap[i]->used2 - now > lumpcache.heap[k]->used2 - now)
+                        sysfatal("lc: bad heap ordering");
+        }
+
+        refed = 0;
+        size = 0;
+        for(i = 0; i < lumpcache.nblocks; i++){
+                b = &lumpcache.blocks[i];
+                if(b->data == nil && b->size != 0)
+                        sysfatal("bad size: %d data=%p", b->size, b->data);
+                if(b->ref && b->heap == TWID32)
+                        refed++;
+                if(b->type != TWID8){
+                        findblock(b);
+                        size += b->size;
+                }
+                if(b->heap != TWID32
+                && lumpcache.heap[b->heap] != b)
+                        sysfatal("lc: spurious heap value");
+        }
+        if(lumpcache.avail != lumpcache.allowed - size){
+                fprint(2, "mismatched available=%d and allowed=%d - used=%d space", lumpcache.avail, lumpcache.allowed, size);
+                *(int*)0=0;
+        }
+
+        nfree = 0;
+        for(b = lumpcache.free; b != nil; b = b->next){
+                if(b->type != TWID8 || b->heap != TWID32)
+                        sysfatal("lc: bad free list");
+                nfree++;
+        }
+
+        if(lumpcache.nheap + nfree + refed != lumpcache.nblocks)
+                sysfatal("lc: missing blocks: %d %d %d %d", lumpcache.nheap, refed, nfree, lumpcache.nblocks);
+}
diff --git a/src/cmd/venti/srv/lumpqueue.c b/src/cmd/venti/srv/lumpqueue.c
t@@ -0,0 +1,187 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+typedef struct LumpQueue        LumpQueue;
+typedef struct WLump                WLump;
+
+enum
+{
+        MaxLumpQ        = 1 << 3        /* max. lumps on a single write queue, must be pow 2 */
+};
+
+struct WLump
+{
+        Lump        *u;
+        Packet        *p;
+        int        creator;
+        int        gen;
+        uint        ms;
+};
+
+struct LumpQueue
+{
+        QLock        lock;
+        Rendez         flush;
+        Rendez        full;
+        Rendez        empty;
+        WLump        q[MaxLumpQ];
+        int        w;
+        int        r;
+};
+
+static LumpQueue        *lumpqs;
+static int                nqs;
+
+static QLock                glk;
+static int                gen;
+
+static void        queueproc(void *vq);
+
+int
+initlumpqueues(int nq)
+{
+        LumpQueue *q;
+
+        int i;
+        nqs = nq;
+
+        lumpqs = MKNZ(LumpQueue, nq);
+
+        for(i = 0; i < nq; i++){
+                q = &lumpqs[i];
+                q->full.l = &q->lock;
+                q->empty.l = &q->lock;
+                q->flush.l = &q->lock;
+
+                if(vtproc(queueproc, q) < 0){
+                        seterr(EOk, "can't start write queue slave: %r");
+                        return -1;
+                }
+                if(vtproc(queueproc, q) < 0){
+                        seterr(EOk, "can't start write queue slave: %r");
+                        return -1;
+                }
+                if(vtproc(queueproc, q) < 0){
+                        seterr(EOk, "can't start write queue slave: %r");
+                        return -1;
+                }
+                if(vtproc(queueproc, q) < 0){
+                        seterr(EOk, "can't start write queue slave: %r");
+                        return -1;
+                }
+                if(vtproc(queueproc, q) < 0){
+                        seterr(EOk, "can't start write queue slave: %r");
+                        return -1;
+                }
+        }
+
+        return 0;
+}
+
+/*
+ * queue a lump & it's packet data for writing
+ */
+int
+queuewrite(Lump *u, Packet *p, int creator, uint ms)
+{
+        LumpQueue *q;
+        int i;
+
+        trace(TraceProc, "queuewrite");
+        i = indexsect(mainindex, u->score);
+        if(i < 0 || i >= nqs){
+                seterr(EBug, "internal error: illegal index section in queuewrite");
+                return -1;
+        }
+
+        q = &lumpqs[i];
+
+        qlock(&q->lock);
+        while(q->r == ((q->w + 1) & (MaxLumpQ - 1))){
+                trace(TraceProc, "queuewrite sleep");
+                rsleep(&q->full);
+        }
+
+        q->q[q->w].u = u;
+        q->q[q->w].p = p;
+        q->q[q->w].creator = creator;
+        q->q[q->w].ms = ms;
+        q->q[q->w].gen = gen;
+        q->w = (q->w + 1) & (MaxLumpQ - 1);
+
+        trace(TraceProc, "queuewrite wakeup");
+        rwakeup(&q->empty);
+
+        qunlock(&q->lock);
+
+        return 0;
+}
+
+void
+flushqueue(void)
+{
+        int i;
+        LumpQueue *q;
+
+        if(!lumpqs)
+                return;
+
+        trace(TraceProc, "flushqueue");
+
+        qlock(&glk);
+        gen++;
+        qunlock(&glk);
+
+        for(i=0; insects; i++){
+                q = &lumpqs[i];
+                qlock(&q->lock);
+                while(q->w != q->r && gen - q->q[q->r].gen > 0){
+                        trace(TraceProc, "flushqueue sleep q%d", i);
+                        rsleep(&q->flush);
+                }
+                qunlock(&q->lock);
+        }
+}
+        
+static void
+queueproc(void *vq)
+{
+        LumpQueue *q;
+        Lump *u;
+        Packet *p;
+        int creator;
+        uint ms;
+
+        threadsetname("queueproc");
+
+        q = vq;
+        for(;;){
+                qlock(&q->lock);
+                while(q->w == q->r){
+                        trace(TraceProc, "queueproc sleep empty");
+                        rsleep(&q->empty);
+                }
+
+                u = q->q[q->r].u;
+                p = q->q[q->r].p;
+                creator = q->q[q->r].creator;
+                ms = q->q[q->r].ms;
+
+                q->r = (q->r + 1) & (MaxLumpQ - 1);
+                trace(TraceProc, "queueproc wakeup flush");
+                rwakeupall(&q->flush);
+
+                trace(TraceProc, "queueproc wakeup full");
+                rwakeup(&q->full);
+
+                qunlock(&q->lock);
+
+                trace(TraceProc, "queueproc writelump %V", u->score);
+                if(writeqlump(u, p, creator, ms) < 0)
+                        fprint(2, "failed to write lump for %V: %r", u->score);
+                trace(TraceProc, "queueproc wrotelump %V", u->score);
+
+                putlump(u);
+        }
+}
diff --git a/src/cmd/venti/srv/mkfile b/src/cmd/venti/srv/mkfile
t@@ -0,0 +1,146 @@
+<$PLAN9/src/mkhdr
+CC=9c
+
+AR=ar
+
+LIBOFILES=\
+        arena.$O\
+        arenas.$O\
+        bloom.$O\
+        buildbuck.$O\
+        clump.$O\
+        config.$O\
+        conv.$O\
+        dcache.$O\
+        dump.$O\
+        graph.$O\
+        httpd.$O\
+        icache.$O\
+        icachewrite.$O\
+        ifile.$O\
+        index.$O\
+        lump.$O\
+        lumpcache.$O\
+        lumpqueue.$O\
+        part.$O\
+        png.$O\
+        round.$O\
+        score.$O\
+        sortientry.$O\
+        stats.$O\
+        syncarena.$O\
+        syncindex0.$O\
+        trace.$O\
+        unwhack.$O\
+        utils.$O\
+        unittoull.$O\
+        whack.$O\
+        xml.$O\
+        zblock.$O\
+        zeropart.$O\
+
+SLIB=libvs.a
+
+LIB=$SLIB
+
+HFILES=        dat.h\
+        fns.h\
+        stdinc.h\
+
+TARG=\
+        venti\
+        fmtarenas\
+        fmtbloom\
+        fmtisect\
+        fmtindex\
+        buildindex\
+        checkarenas\
+        checkindex\
+        clumpstats\
+        findscore\
+        rdarena\
+        wrarena\
+        syncindex\
+        printarena\
+        verifyarena\
+
+OFILES=
+
+BIN=$BIN/venti
+
+it:V: $O.venti
+
+$O.venti: # debugmalloc2.$O # debugmalloc.$O #_p9dir.$O debugmalloc.$O
+
+CLEANFILES=$CLEANFILES $SLIB
+
+<$PLAN9/src/mkmany
+
+$SLIB: $LIBOFILES
+        $AR rvc $SLIB $LIBOFILES
+
+# xml.c:D:        mkxml dat.h
+#         ./mkxml dat.h > xml.c
+
+ainstall:V: ${TARG:%=%.ainstall}
+
+%.ainstall:V:        $O.%
+        scp $prereq amsterdam:/usr/local/bin/venti/$stem
+
+test:VQ: ${TARG:%=o.%}
+        slay o.venti|rc
+        vtmp=/home/tmp
+        echo '**********' FMTARENAS
+        ./o.fmtarenas -a 40M -b 8k arenas $vtmp/arena
+        echo '**********' FMTBLOOM
+        ./o.fmtbloom -s 10M $vtmp/bloom
+        echo '**********' FMTISECT
+        ./o.fmtisect -b 8k isect $vtmp/isect
+        (
+                echo index main
+                echo isect $vtmp/isect
+                echo arenas $vtmp/arena
+                echo bloom $vtmp/bloom
+                echo webroot $HOME/src/venti/www
+                echo mem 64M
+                echo icmem 64M
+                echo bcmem 64M
+        ) >vtmp.conf
+        echo '**********' FMTINDEX
+        ./o.fmtindex vtmp.conf
+        echo '**********' VENTI
+        # ./o.venti -c vtmp.conf -B 64M -I 64M -C 64M -a 'tcp!*!17034' -h 'tcp!*!8001'  >a 2>&1 &
+        ./o.venti -c vtmp.conf -a 'tcp!*!17034' -h 'tcp!*!8001'  >a 2>&1 &
+        sleep 5
+        echo '**********' VAC
+        venti='tcp!127.0.0.1!17034' export venti
+        9 time vac /usr/local/plan9 >a.vac
+        case ${websync:-no} in
+        yes)
+                echo '**********' SYNC VIA WEB
+                hget http://127.0.0.1:8001/flushdcache
+                hget http://127.0.0.1:8001/flushicache
+                hget http://127.0.0.1:8001/flushdcache
+                echo '**********' KILL VENTI
+                killall -9 o.venti
+                ;;
+        no)
+                echo '**********' KILL VENTI
+                killall -9 o.venti
+                echo '**********' SYNCINDEX
+                ./o.syncindex -B64M -I64M -f vtmp.conf
+                ;;
+        esac
+        echo '**********' CHECKINDEX
+        ./o.checkindex -B64M vtmp.conf /home/tmp/check >check.out
+        wc check.out
+
+luadisk.o: luadisk.c
+        gcc -c -ggdb -Wall -I/usr/include/lua50 luadisk.c
+
+libluadisk.so: luadisk.o
+        gcc -shared -o $target luadisk.o -llua50 -llualib50
+
+$O.xwrarena: xwrarena.$O
+        $LD -o $target xwrarena.$O 
+
diff --git a/src/cmd/venti/srv/part.c b/src/cmd/venti/srv/part.c
t@@ -0,0 +1,383 @@
+#ifdef PLAN9PORT        /* SORRY! */
+#include 
+#include 
+#include 
+#endif
+#include "stdinc.h"
+#include 
+#include "dat.h"
+#include "fns.h"
+
+u32int        maxblocksize;
+int        readonly;
+
+static int
+strtoullsuf(char *p, char **pp, int rad, u64int *u)
+{
+        u64int v;
+
+        if(!isdigit(*p))
+                return -1;
+        v = strtoull(p, &p, rad);
+        switch(*p){
+        case 'k':
+        case 'K':
+                v *= 1024;
+                p++;
+                break;
+        case 'm':
+        case 'M':
+                v *= 1024*1024;
+                p++;
+                break;
+        case 'g':
+        case 'G':
+                v *= 1024*1024*1024;
+                p++;
+                break;
+        case 't':
+        case 'T':
+                v *= 1024*1024;
+                v *= 1024*1024;
+                p++;
+                break;
+        }
+        *pp = p;
+        *u = v;
+        return 0;
+}
+        
+static int
+parsepart(char *name, char **file, u64int *lo, u64int *hi)
+{
+        char *p;
+
+        *file = estrdup(name);
+        if((p = strrchr(*file, ':')) == nil){
+                *lo = 0;
+                *hi = 0;
+                return 0;
+        }
+        *p++ = 0;
+        if(*p == '-')
+                *lo = 0;
+        else{
+                if(strtoullsuf(p, &p, 0, lo) < 0){
+                        free(*file);
+                        return -1;
+                }
+        }
+        if(*p == '-')
+                p++;
+        if(*p == 0){
+                *hi = 0;
+                return 0;
+        }
+        if(strtoullsuf(p, &p, 0, hi) < 0 || *p != 0){
+                free(*file);
+                return -1;
+        }
+        return 0;
+}
+
+Part*
+initpart(char *name, int mode)
+{
+        Part *part;
+        Dir *dir;
+        char *file;
+        u64int lo, hi;
+
+        if(parsepart(name, &file, &lo, &hi) < 0)
+                return nil;
+        trace(TraceDisk, "initpart %s file %s lo 0x%llx hi 0x%llx", name, file, lo, hi);
+        part = MKZ(Part);
+        part->name = estrdup(name);
+        part->filename = estrdup(file);
+        if(readonly){
+                mode &= (OREAD|OWRITE|ORDWR);
+                mode |= OREAD;
+        }
+        part->fd = open(file, mode);
+        if(part->fd < 0){
+                if((mode&(OREAD|OWRITE|ORDWR)) == ORDWR)
+                        part->fd = open(file, (mode&~ORDWR)|OREAD);
+                if(part->fd < 0){
+                        freepart(part);
+                        fprint(2, "can't open partition='%s': %r\n", file);
+                        seterr(EOk, "can't open partition='%s': %r", file);
+                        fprint(2, "%r\n");
+                        free(file);
+                        return nil;
+                }
+                fprint(2, "warning: %s opened for reading only\n", name);
+        }
+        part->offset = lo;
+        dir = dirfstat(part->fd);
+        if(dir == nil){
+                freepart(part);
+                seterr(EOk, "can't stat partition='%s': %r", file);
+                free(file);
+                return nil;
+        }
+        if(dir->length == 0){
+                free(dir);
+                freepart(part);
+                seterr(EOk, "can't determine size of partition %s", file);
+                free(file);
+                return nil;
+        }
+        if(dir->length < hi || dir->length < lo){
+                freepart(part);
+                seterr(EOk, "partition '%s': bounds out of range (max %lld)", name, dir->length);
+                free(dir);
+                free(file);
+                return nil;
+        }
+        if(hi == 0)
+                hi = dir->length;
+        part->size = hi - part->offset;
+#ifdef _LIBC_H_
+        {
+                struct statfs sfs;
+                if(fstatfs(part->fd, &sfs) >= 0)
+                        part->fsblocksize = sfs.f_bsize;
+        }
+#endif
+        free(dir);
+        return part;
+}
+
+void
+freepart(Part *part)
+{
+        if(part == nil)
+                return;
+        if(part->fd >= 0)
+                close(part->fd);
+        free(part->name);
+        free(part);
+}
+
+void
+partblocksize(Part *part, u32int blocksize)
+{
+        if(part->blocksize)
+                sysfatal("resetting partition=%s's block size", part->name);
+        part->blocksize = blocksize;
+        if(blocksize > maxblocksize)
+                maxblocksize = blocksize;
+}
+
+/*
+ * Read/write some amount of data between a block device or file and a memory buffer.
+ *
+ * Most Unix systems require that when accessing a block device directly,
+ * the buffer, offset, and count are all multiples of the device block size,
+ * making this a lot more complicated than it otherwise would be.
+ * 
+ * Most of our callers will make things easy on us, but for some callers it's best
+ * if we just do the work here, with only one place to get it right (hopefully).
+ * 
+ * If everything is aligned properly, prwb will try to do big transfers in the main 
+ * body of the loop: up to MaxIo bytes at a time.  If everything isn't aligned properly,
+ * we work one block at a time.
+ */
+#undef min
+#define min(a, b) ((a) < (b) ? (a) : (b))
+int
+prwb(char *name, int fd, int isread, u64int offset, void *vbuf, u32int count, u32int blocksize)
+{
+        char *op;
+        u8int *buf, *tmp, *freetmp, *dst;
+        u32int c, delta, icount, opsize;
+        int r;
+
+        buf = vbuf;
+        tmp = nil;
+        freetmp = nil;
+        icount = count;
+        opsize = blocksize;
+
+        if(count == 0){
+                logerr(EStrange, "pwrb %s called to %s 0 bytes", name, isread ? "read" : "write");
+                return 0;
+        }
+
+        assert(blocksize > 0);
+
+        /* allocate blocksize-aligned temp buffer if needed */
+        if((ulong)offset%blocksize || (ulong)buf%blocksize || count%blocksize){
+                if((freetmp = malloc(blocksize*2)) == nil)
+                        return -1;
+                tmp = freetmp;
+                tmp += blocksize - (ulong)tmp%blocksize;
+        }
+
+        /* handle beginning fringe */
+        if((delta = (ulong)offset%blocksize) != 0){
+                assert(tmp != nil);
+                if((r=pread(fd, tmp, blocksize, offset-delta)) != blocksize){
+                        dst = tmp;
+                        offset = offset-delta;
+                        op = "read";
+                        goto Error;
+                }
+                c = min(count, blocksize-delta);
+                assert(c > 0 && c < blocksize);
+                if(isread)
+                        memmove(buf, tmp+delta, c);
+                else{
+                        memmove(tmp+delta, buf, c);
+                        if((r=pwrite(fd, tmp, blocksize, offset-delta)) != blocksize){
+                                dst = tmp;
+                                offset = offset-delta;
+                                op = "read";
+                                goto Error;
+                        }
+                }
+                assert(c > 0);
+                offset += c;
+                buf += c;
+                count -= c;
+        }
+
+        /* handle full blocks */
+        while(count >= blocksize){
+                assert((ulong)offset%blocksize == 0);
+                if((ulong)buf%blocksize){
+                        assert(tmp != nil);
+                        dst = tmp;
+                        opsize = blocksize;
+                }else{
+                        dst = buf;
+                        opsize = count - count%blocksize;
+                        if(opsize > MaxIo)
+                                opsize = MaxIo;
+                }
+                if(isread){
+                        if((r=pread(fd, dst, opsize, offset))<=0 || r%blocksize){
+                                op = "read";
+                                goto Error;
+                        }
+                        if(dst == tmp){
+                                assert(r == blocksize);
+                                memmove(buf, tmp, blocksize);
+                        }
+                }else{
+                        if(dst == tmp){
+                                assert(opsize == blocksize);
+                                memmove(dst, buf, blocksize);
+                        }
+                        if((r=pwrite(fd, dst, opsize, offset))<=0 || r%blocksize){
+                                op = "write";
+                                goto Error;
+                        }
+                        if(dst == tmp)
+                                assert(r == blocksize);
+                }
+                assert(r > 0);
+                offset += r;
+                buf += r;
+                count -= r;
+        }
+
+        /* handle ending fringe */
+        if(count > 0){
+                assert((ulong)offset%blocksize == 0);
+                assert(tmp != nil);
+                /*
+                 * Complicated condition: if we're reading it's okay to get less than
+                 * a block as long as it's enough to satisfy the read - maybe this is
+                 * a normal file.  (We never write to normal files, or else things would
+                 * be even more complicated.)
+                 */
+                r = pread(fd, tmp, blocksize, offset);
+                if((isread && r < count) || (!isread && r != blocksize)){
+print("FAILED isread=%d r=%d count=%d blocksize=%d\n", isread, r, count, blocksize);
+                        dst = tmp;
+                        op = "read";
+                        goto Error;
+                }
+                if(isread)
+                        memmove(buf, tmp, count);
+                else{
+                        memmove(tmp, buf, count);
+                        if(pwrite(fd, tmp, opsize, offset) != blocksize){
+                                dst = tmp;
+                                op = "write";
+                                goto Error;
+                        }
+                }
+        }
+        if(freetmp)
+                free(freetmp);
+        return icount;
+
+Error:
+        seterr(EAdmin, "%s %s offset 0x%llux count %ud buf %p returned %d: %r",
+                op, name, offset, opsize, dst, r);
+        if(freetmp)
+                free(freetmp);
+        return -1;
+}
+
+int
+rwpart(Part *part, int isread, u64int offset, u8int *buf, u32int count)
+{
+        u32int blocksize;
+
+        trace(TraceDisk, "%s %s %ud at 0x%llx", 
+                isread ? "read" : "write", part->name, count, offset);
+        if(offset >= part->size || offset+count > part->size){
+                seterr(EStrange, "out of bounds %s offset 0x%llux count %ud to partition %s size 0x%llux",
+                        isread ? "read" : "write", offset, count, part->name, part->size);
+                return -1;
+        }
+
+        blocksize = part->fsblocksize;
+        if(blocksize == 0)
+                blocksize = part->blocksize;
+        if(blocksize == 0)
+                blocksize = 4096;
+
+        return prwb(part->filename, part->fd, isread, part->offset+offset, buf, count, blocksize);
+}
+
+int
+readpart(Part *part, u64int offset, u8int *buf, u32int count)
+{
+        return rwpart(part, 1, offset, buf, count);
+}
+
+int
+writepart(Part *part, u64int offset, u8int *buf, u32int count)
+{
+        return rwpart(part, 0, offset, buf, count);
+}
+
+ZBlock*
+readfile(char *name)
+{
+        Part *p;
+        ZBlock *b;
+
+        p = initpart(name, OREAD);
+        if(p == nil)
+                return nil;
+        b = alloczblock(p->size, 0, p->blocksize);
+        if(b == nil){
+                seterr(EOk, "can't alloc %s: %r", name);
+                freepart(p);
+                return nil;
+        }
+        if(readpart(p, 0, b->data, p->size) < 0){
+                seterr(EOk, "can't read %s: %r", name);
+                freepart(p);
+                freezblock(b);
+                return nil;
+        }
+        freepart(p);
+        return b;
+}
+
diff --git a/src/cmd/venti/srv/png.c b/src/cmd/venti/srv/png.c
t@@ -0,0 +1,241 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+enum
+{
+        IDATSIZE        = 20000,
+        FilterNone = 0
+};
+
+typedef struct ZlibR ZlibR;
+typedef struct ZlibW ZlibW;
+
+struct ZlibR
+{
+        uchar *data;
+        int width;
+        int dx;
+        int dy;
+        int x;
+        int y;
+        int pixwid;
+};
+
+struct ZlibW
+{
+        Hio *io;
+        uchar *buf;
+        uchar *b;
+        uchar *e;
+};
+
+static ulong *crctab;
+static uchar PNGmagic[] = { 137, 'P', 'N', 'G', '\r', '\n', 26, '\n'};
+
+static void
+put4(uchar *a, ulong v)
+{
+        a[0] = v>>24;
+        a[1] = v>>16;
+        a[2] = v>>8;
+        a[3] = v;
+}
+
+static void
+chunk(Hio *io, char *type, uchar *d, int n)
+{
+        uchar buf[4];
+        ulong crc = 0;
+
+        if(strlen(type) != 4)
+                return;
+        put4(buf, n);
+        hwrite(io, buf, 4);
+        hwrite(io, type, 4);
+        hwrite(io, d, n);
+        crc = blockcrc(crctab, crc, type, 4);
+        crc = blockcrc(crctab, crc, d, n);
+        put4(buf, crc);
+        hwrite(io, buf, 4);
+}
+
+static int
+zread(void *va, void *buf, int n)
+{
+        int a, i, pixels, pixwid;
+        uchar *b, *e, *img;
+        ZlibR *z;
+
+        z = va;
+        pixwid = z->pixwid;
+        b = buf;
+        e = b+n;
+        while(b+pixwid <= e){
+                if(z->y >= z->dy)
+                        break;
+                if(z->x == 0)
+                        *b++ = FilterNone;
+                pixels = (e-b)/pixwid;
+                if(pixels > z->dx - z->x)
+                        pixels = z->dx - z->x;
+                img = z->data + z->width*z->y + pixwid*z->x;
+                memmove(b, img, pixwid*pixels);
+                if(pixwid == 4){
+                        /*
+                         * Convert to non-premultiplied alpha.
+                         */
+                        for(i=0; i= a)
+                                                b[0] = a;
+                                        b[0] = (b[0]*255)/a;
+                                        if(b[1] >= a)
+                                                b[1] = a;
+                                        b[1] = (b[1]*255)/a;
+                                        if(b[2] >= a)
+                                                b[2] = a;
+                                        b[2] = (b[2]*255)/a;
+                                }
+                        }
+                }else        
+                        b += pixwid*pixels;
+
+                z->x += pixels;
+                if(z->x >= z->dx){
+                        z->x = 0;
+                        z->y++;
+                }
+        }
+        return b - (uchar*)buf;
+}
+
+static void
+IDAT(ZlibW *z)
+{
+        chunk(z->io, "IDAT", z->buf, z->b - z->buf);
+        z->b = z->buf;
+}
+
+static int
+zwrite(void *va, void *buf, int n)
+{
+        int m;
+        uchar *b, *e;
+        ZlibW *z;
+
+        z = va;
+        b = buf;
+        e = b+n;
+
+        while(b < e){
+                m = z->e - z->b;
+                if(m > e - b)
+                        m = e - b;
+                memmove(z->b, b, m);
+                z->b += m;
+                b += m;
+                if(z->b >= z->e)
+                        IDAT(z);
+        }
+        return n;
+}
+
+static Memimage*
+memRGBA(Memimage *i)
+{
+        Memimage *ni;
+        char buf[32];
+        ulong dst;
+        
+        /*
+         * [A]BGR because we want R,G,B,[A] in big-endian order.  Sigh.
+         */
+        chantostr(buf, i->chan);
+        if(strchr(buf, 'a'))
+                dst = ABGR32;
+        else
+                dst = BGR24;
+                
+        if(i->chan == dst)
+                return i;
+
+        qlock(&memdrawlock);
+        ni = allocmemimage(i->r, dst);
+        if(ni)
+                memimagedraw(ni, ni->r, i, i->r.min, nil, i->r.min, S);
+        qunlock(&memdrawlock);
+        return ni;
+}
+
+int
+writepng(Hio *io, Memimage *m)
+{
+        static int first = 1;
+        static QLock lk;
+        uchar buf[200], *h;
+        Memimage *rgb;
+        ZlibR zr;
+        ZlibW zw;
+
+        if(first){
+                qlock(&lk);
+                if(first){
+                        deflateinit();
+                        crctab = mkcrctab(0xedb88320);
+                        first = 0;
+                }
+                qunlock(&lk);
+        }
+
+        rgb = memRGBA(m);
+        if(rgb == nil)
+                return -1;
+
+        hwrite(io, PNGmagic, sizeof PNGmagic);
+        
+        /* IHDR chunk */
+        h = buf;
+        put4(h, Dx(m->r)); h += 4;
+        put4(h, Dy(m->r)); h += 4;
+        *h++ = 8;        /* 8 bits per channel */
+        if(rgb->chan == BGR24)
+                *h++ = 2;                /* RGB */
+        else
+                *h++ = 6;                /* RGBA */
+        *h++ = 0;        /* compression - deflate */
+        *h++ = 0;        /* filter - none */
+        *h++ = 0;        /* interlace - none */
+        chunk(io, "IHDR", buf, h-buf);
+
+        /* image data */
+        zr.dx = Dx(m->r);
+        zr.dy = Dy(m->r);
+        zr.width = rgb->width * sizeof(ulong);
+        zr.data = rgb->data->bdata;
+        zr.x = 0;
+        zr.y = 0;
+        zr.pixwid = chantodepth(rgb->chan)/8;
+        zw.io = io;
+        zw.buf = vtmalloc(IDATSIZE);
+        zw.b = zw.buf;
+        zw.e = zw.b + IDATSIZE;
+        if(deflatezlib(&zw, zwrite, &zr, zread, 6, 0) < 0){
+                free(zw.buf);
+                return -1;
+        }
+        if(zw.b > zw.buf)
+                IDAT(&zw);
+        free(zw.buf);
+        chunk(io, "IEND", nil, 0);
+
+        if(m != rgb){
+                qlock(&memdrawlock);
+                freememimage(rgb);
+                qunlock(&memdrawlock);
+        }
+        return 0;
+}
diff --git a/src/cmd/venti/srv/printarena.c b/src/cmd/venti/srv/printarena.c
t@@ -0,0 +1,130 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+void
+usage(void)
+{
+        fprint(2, "usage: printarena arenafile [offset]\n");
+        threadexitsall("usage");
+}
+
+static void
+rdarena(Arena *arena, u64int offset)
+{
+        u64int a, aa, e;
+        u32int magic;
+        Clump cl;
+        uchar score[VtScoreSize];
+        ZBlock *lump;
+
+        printarena(2, arena);
+
+        a = arena->base;
+        e = arena->base + arena->size;
+        if(offset != ~(u64int)0) {
+                if(offset >= e-a)
+                        sysfatal("bad offset %llud >= %llud\n",
+                                offset, e-a);
+                aa = offset;
+        } else
+                aa = 0;
+
+        for(; aa < e; aa += ClumpSize+cl.info.size) {
+                magic = clumpmagic(arena, aa);
+                if(magic == ClumpFreeMagic)
+                        break;
+                if(magic != arena->clumpmagic) {
+                        fprint(2, "illegal clump magic number %#8.8ux offset %llud\n",
+                                magic, aa);
+                        break;
+                }
+                lump = loadclump(arena, aa, 0, &cl, score, 0);
+                if(lump == nil) {
+                        fprint(2, "clump %llud failed to read: %r\n", aa);
+                        break;
+                }
+                if(cl.info.type != VtCorruptType) {
+                        scoremem(score, lump->data, cl.info.uncsize);
+                        if(scorecmp(cl.info.score, score) != 0) {
+                                fprint(2, "clump %llud has mismatched score\n", aa);
+                                break;
+                        }
+                        if(vttypevalid(cl.info.type) < 0) {
+                                fprint(2, "clump %llud has bad type %d\n", aa, cl.info.type);
+                                break;
+                        }
+                }
+                print("%22llud %V %3d %5d\n", aa, score, cl.info.type, cl.info.uncsize);
+                freezblock(lump);
+        }
+        print("end offset %llud\n", aa);
+}
+
+void
+threadmain(int argc, char *argv[])
+{
+        char *file;
+        Arena *arena;
+        u64int offset, aoffset;
+        Part *part;
+        Dir *d;
+        uchar buf[8192];
+        ArenaHead head;
+
+        readonly = 1;        /* for part.c */
+        aoffset = 0;
+        ARGBEGIN{
+        case 'o':
+                aoffset = strtoull(EARGF(usage()), 0, 0);
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        offset = ~(u64int)0;
+        switch(argc) {
+        default:
+                usage();
+        case 2:
+                offset = strtoull(argv[1], 0, 0);
+                /* fall through */
+        case 1:
+                file = argv[0];
+        }
+
+
+        ventifmtinstall();
+        statsinit();
+
+        if((d = dirstat(file)) == nil)
+                sysfatal("can't stat file %s: %r", file);
+
+        part = initpart(file, OREAD|ODIRECT);
+        if(part == nil)
+                sysfatal("can't open file %s: %r", file);
+        if(readpart(part, aoffset, buf, sizeof buf) < 0)
+                sysfatal("can't read file %s: %r", file);
+
+        if(unpackarenahead(&head, buf) < 0)
+                sysfatal("corrupted arena header: %r");
+
+        print("# arena head version=%d name=%.*s blocksize=%d size=%lld clumpmagic=0x%.8ux\n",
+                head.version, ANameSize, head.name, head.blocksize,
+                head.size, head.clumpmagic);
+
+        if(aoffset+head.size > d->length)
+                sysfatal("arena is truncated: want %llud bytes have %llud\n",
+                        head.size, d->length);
+
+        partblocksize(part, head.blocksize);
+        initdcache(8 * MaxDiskBlock);
+
+        arena = initarena(part, aoffset, head.size, head.blocksize);
+        if(arena == nil)
+                sysfatal("initarena: %r");
+
+        rdarena(arena, offset);
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/srv/printarenas.c b/src/cmd/venti/srv/printarenas.c
t@@ -0,0 +1,113 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+#include 
+
+Biobuf bout;
+
+static void
+pie(IEntry *ie)
+{
+        Bprint(&bout, "%22lld %V %3d %5d\n",
+                ie->ia.addr, ie->score, ie->ia.type, ie->ia.size);
+}
+
+void
+usage(void)
+{
+        fprint(2, "usage: printarenas [-B blockcachesize] config [arenaname...]\n");
+        threadexitsall(0);
+}
+
+Config conf;
+
+int
+shoulddump(char *name, int argc, char **argv)
+{
+        int i;
+
+        if(argc == 0)
+                return 1;
+        for(i=0; imemstats.clumps; clump += n){
+                n = ClumpChunks;
+                if(n > arena->memstats.clumps - clump)
+                        n = arena->memstats.clumps - clump;
+                if(readclumpinfos(arena, clump, cis, n) != n){
+                        fprint(2, "arena directory read failed: %r\n");
+                        break;
+                }
+
+                for(i = 0; i < n; i++){
+                        ci = &cis[i];
+                        ie.ia.type = ci->type;
+                        ie.ia.size = ci->uncsize;
+                        ie.ia.addr = a;
+                        a += ci->size + ClumpSize;
+                        ie.ia.blocks = (ci->size + ClumpSize + (1 << ABlockLog) - 1) >> ABlockLog;
+                        scorecp(ie.score, ci->score);
+                        pie(&ie);
+                }
+        }
+        free(cis);
+}
+
+void
+threadmain(int argc, char *argv[])
+{
+        int i;
+        Index *ix;
+        u32int bcmem;
+
+        bcmem = 0;
+        ARGBEGIN{
+        case 'B':
+                bcmem = unittoull(ARGF());
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        if(argc < 1)
+                usage();
+
+        ventifmtinstall();
+
+        if(initventi(argv[0], &conf) < 0)
+                sysfatal("can't init venti: %r");
+
+        if(bcmem < maxblocksize * (mainindex->narenas + mainindex->nsects * 4 + 16))
+                bcmem = maxblocksize * (mainindex->narenas + mainindex->nsects * 4 + 16);
+        if(0) fprint(2, "initialize %d bytes of disk block cache\n", bcmem);
+        initdcache(bcmem);
+
+        Binit(&bout, 1, OWRITE);
+        ix = mainindex;
+        for(i=0; inarenas; i++)
+                if(shoulddump(ix->arenas[i]->name, argc-1, argv+1))
+                        dumparena(ix->arenas[i], ix->amap[i].start);
+        Bterm(&bout);
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/srv/printindex.c b/src/cmd/venti/srv/printindex.c
t@@ -0,0 +1,99 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+#include 
+
+Biobuf bout;
+
+static void
+pie(IEntry *ie)
+{
+        Bprint(&bout, "%22lld %V %3d %5d\n",
+                ie->ia.addr, ie->score, ie->ia.type, ie->ia.size);
+}
+
+void
+usage(void)
+{
+        fprint(2, "usage: printindex [-B blockcachesize] config [isectname...]\n");
+        threadexitsall(0);
+}
+
+Config conf;
+
+int
+shoulddump(char *name, int argc, char **argv)
+{
+        int i;
+
+        if(argc == 0)
+                return 1;
+        for(i=0; iblocksize);
+        for(i=0; iblocks; i++){
+                off = is->blockbase+(u64int)is->blocksize*i;
+                if(readpart(is->part, off, buf, is->blocksize) < 0)
+                        fprint(2, "read %s at 0x%llux: %r\n", is->part->name, off);
+                else{
+                        unpackibucket(&ib, buf, is->bucketmagic);
+                        for(j=0; jnarenas + mainindex->nsects * 4 + 16))
+                bcmem = maxblocksize * (mainindex->narenas + mainindex->nsects * 4 + 16);
+        if(0) fprint(2, "initialize %d bytes of disk block cache\n", bcmem);
+        initdcache(bcmem);
+
+        ix = mainindex;
+        Binit(&bout, 1, OWRITE);
+        for(i=0; insects; i++)
+                if(shoulddump(ix->sects[i]->name, argc-1, argv+1))
+                        dumpisect(ix->sects[i]);
+        Bterm(&bout);
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/srv/printmap.c b/src/cmd/venti/srv/printmap.c
t@@ -0,0 +1,42 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+void
+usage(void)
+{
+        fprint(2, "usage: printmap [-B blockcachesize] config\n");
+        threadexitsall("usage");
+}
+
+Config conf;
+
+void
+threadmain(int argc, char *argv[])
+{
+        u32int bcmem;
+        int fix;
+
+        fix = 0;
+        bcmem = 0;
+        ARGBEGIN{
+        case 'B':
+                bcmem = unittoull(ARGF());
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        if(!fix)
+                readonly = 1;
+
+        if(argc != 1)
+                usage();
+
+        if(initventi(argv[0], &conf) < 0)
+                sysfatal("can't init venti: %r");
+
+        printindex(1, mainindex);
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/srv/rdarena.c b/src/cmd/venti/srv/rdarena.c
t@@ -0,0 +1,91 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+static int        verbose;
+
+void
+usage(void)
+{
+        fprint(2, "usage: rdarena [-v] arenapart arena\n");
+        threadexitsall(0);
+}
+
+static void
+rdarena(Arena *arena)
+{
+        ZBlock *b;
+        u64int a, e;
+        u32int bs;
+
+        fprint(2, "copying %s to standard output\n", arena->name);
+        printarena(2, arena);
+
+        bs = MaxIoSize;
+        if(bs < arena->blocksize)
+                bs = arena->blocksize;
+
+        b = alloczblock(bs, 0, arena->blocksize);
+        e = arena->base + arena->size + arena->blocksize;
+        for(a = arena->base - arena->blocksize; a + arena->blocksize <= e; a += bs){
+                if(a + bs > e)
+                        bs = arena->blocksize;
+                if(readpart(arena->part, a, b->data, bs) < 0)
+                        fprint(2, "can't copy %s, read at %lld failed: %r\n", arena->name, a);        
+                if(write(1, b->data, bs) != bs)
+                        sysfatal("can't copy %s, write at %lld failed: %r", arena->name, a);
+        }
+
+        freezblock(b);
+}
+
+void
+threadmain(int argc, char *argv[])
+{
+        ArenaPart *ap;
+        Part *part;
+        char *file, *aname;
+        int i;
+
+        ventifmtinstall();
+        statsinit();
+
+        ARGBEGIN{
+        case 'v':
+                verbose++;
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        readonly = 1;
+
+        if(argc != 2)
+                usage();
+
+        file = argv[0];
+        aname = argv[1];
+
+        part = initpart(file, OREAD|ODIRECT);
+        if(part == nil)
+                sysfatal("can't open partition %s: %r", file);
+
+        ap = initarenapart(part);
+        if(ap == nil)
+                sysfatal("can't initialize arena partition in %s: %r", file);
+
+        if(verbose)
+                printarenapart(2, ap);
+
+        initdcache(8 * MaxDiskBlock);
+
+        for(i = 0; i < ap->narenas; i++){
+                if(strcmp(ap->arenas[i]->name, aname) == 0){
+                        rdarena(ap->arenas[i]);
+                        threadexitsall(0);
+                }
+        }
+
+        sysfatal("couldn't find arena %s\n", aname);
+}
diff --git a/src/cmd/venti/srv/round.c b/src/cmd/venti/srv/round.c
t@@ -0,0 +1,102 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+void
+waitforkick(Round *r)
+{
+        int n;
+
+        qlock(&r->lock);
+        r->last = r->current;
+        assert(r->current+1 == r->next);
+        rwakeupall(&r->finish);
+        while(!r->doanother)
+                rsleep(&r->start);
+        n = r->next++;
+        r->current = n;
+        r->doanother = 0;
+        qunlock(&r->lock);
+}
+
+static void
+_kickround(Round *r, int wait)
+{
+        int n;
+
+        if(!r->doanother)
+                trace(TraceProc, "kick %s", r->name);
+        r->doanother = 1;
+        rwakeup(&r->start);
+        if(wait){
+                n = r->next;
+                while((int)(n - r->last) > 0){
+                        r->doanother = 1;
+                        rwakeup(&r->start);
+                        rsleep(&r->finish);
+                }
+        }
+}
+
+void
+kickround(Round *r, int wait)
+{
+        qlock(&r->lock);
+        _kickround(r, wait);
+        qunlock(&r->lock);
+}
+
+void
+initround(Round *r, char *name, int delay)
+{
+        memset(r, 0, sizeof *r);
+        r->name = name;
+        r->start.l = &r->lock;
+        r->finish.l = &r->lock;
+        r->delaywait.l = &r->lock;
+        r->last = 0;
+        r->current = 0;
+        r->next = 1;
+        r->doanother = 0;
+        r->delaytime = delay;
+}
+
+void
+delaykickround(Round *r)
+{
+        qlock(&r->lock);
+        r->delaykick = 1;
+        rwakeup(&r->delaywait);
+        qunlock(&r->lock);
+}
+
+void
+delaykickroundproc(void *v)
+{
+        Round *r = v;
+        int n;
+
+        threadsetname("delaykickproc %s", r->name);
+        qlock(&r->lock);
+        for(;;){
+                while(r->delaykick == 0){
+                        trace(TraceProc, "sleep");
+                        rsleep(&r->delaywait);
+                }
+
+                n = r->next;
+                qunlock(&r->lock);
+
+                trace(TraceProc, "waitround 0x%ux", (uint)n);
+                sleep(r->delaytime);
+
+                qlock(&r->lock);
+                if(n == r->next){
+                        trace(TraceProc, "kickround 0x%ux", (uint)n);
+                        _kickround(r, 1);
+                }
+
+                trace(TraceProc, "finishround 0x%ux", (uint)n);
+        }
+}
+
diff --git a/src/cmd/venti/srv/score.c b/src/cmd/venti/srv/score.c
t@@ -0,0 +1,43 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+u8int zeroscore[VtScoreSize];
+
+void
+scoremem(u8int *score, u8int *buf, int n)
+{
+        DigestState s;
+
+        memset(&s, 0, sizeof s);
+        sha1(buf, n, score, &s);
+}
+
+static int
+hexv(int c)
+{
+        if(c >= '0' && c <= '9')
+                return c - '0';
+        if(c >= 'a' && c <= 'f')
+                return c - 'a' + 10;
+        if(c >= 'A' && c <= 'F')
+                return c - 'A' + 10;
+        return -1;
+}
+
+int
+strscore(char *s, u8int *score)
+{
+        int i, c, d;
+
+        for(i = 0; i < VtScoreSize; i++){
+                c = hexv(s[2 * i]);
+                if(c < 0)
+                        return -1;
+                d = hexv(s[2 * i + 1]);
+                if(d < 0)
+                        return -1;
+                score[i] = (c << 4) + d;
+        }
+        return s[2 * i] == '\0';
+}
diff --git a/src/cmd/venti/srv/sortientry.c b/src/cmd/venti/srv/sortientry.c
t@@ -0,0 +1,376 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+#include 
+
+typedef struct IEBuck        IEBuck;
+typedef struct IEBucks        IEBucks;
+
+enum
+{
+        ClumpChunks        = 32*1024
+};
+
+struct IEBuck
+{
+        u32int        head;                /* head of chain of chunks on the disk */
+        u32int        used;                /* usage of the last chunk */
+        u64int        total;                /* total number of bytes in this bucket */
+        u8int        *buf;                /* chunk of entries for this bucket */
+};
+
+struct IEBucks
+{
+        Part        *part;
+        u64int        off;                /* offset for writing data in the partition */
+        u32int        chunks;                /* total chunks written to fd */
+        u64int        max;                /* max bytes entered in any one bucket */
+        int        bits;                /* number of bits in initial bucket sort */
+        int        nbucks;                /* 1 << bits, the number of buckets */
+        u32int        size;                /* bytes in each of the buckets chunks */
+        u32int        usable;                /* amount usable for IEntry data */
+        u8int        *buf;                /* buffer for all chunks */
+        u8int        *xbuf;
+        IEBuck        *bucks;
+};
+
+#define        U32GET(p)        (((p)[0]<<24)|((p)[1]<<16)|((p)[2]<<8)|(p)[3])
+#define        U32PUT(p,v)        (p)[0]=(v)>>24;(p)[1]=(v)>>16;(p)[2]=(v)>>8;(p)[3]=(v)
+
+static IEBucks        *initiebucks(Part *part, int bits, u32int size);
+static int        flushiebuck(IEBucks *ib, int b, int reset);
+static int        flushiebucks(IEBucks *ib);
+static u32int        sortiebuck(IEBucks *ib, int b);
+static u64int        sortiebucks(IEBucks *ib);
+static int        sprayientry(IEBucks *ib, IEntry *ie);
+static u32int        readarenainfo(IEBucks *ib, Arena *arena, u64int a, Bloom *b);
+static u32int        readiebuck(IEBucks *ib, int b);
+static void        freeiebucks(IEBucks *ib);
+
+/*
+ * build a sorted file with all IEntries which should be in ix.
+ * assumes the arenas' directories are up to date.
+ * reads each, converts the entries to index entries,
+ * and sorts them.
+ */
+u64int
+sortrawientries(Index *ix, Part *tmp, u64int *base, Bloom *bloom)
+{
+        IEBucks *ib;
+        u64int clumps, sorted;
+        u32int n;
+        int i, ok;
+
+//ZZZ should allow configuration of bits, bucket size
+        ib = initiebucks(tmp, 8, 64*1024);
+        if(ib == nil){
+                seterr(EOk, "can't create sorting buckets: %r");
+                return TWID64;
+        }
+        ok = 0;
+        clumps = 0;
+        fprint(2, "constructing entry list\n");
+        for(i = 0; i < ix->narenas; i++){
+                n = readarenainfo(ib, ix->arenas[i], ix->amap[i].start, bloom);
+                if(n == TWID32){
+                        ok = -1;
+                        break;
+                }
+                clumps += n;
+        }
+        fprint(2, "sorting %lld entries\n", clumps);
+        if(ok == 0){
+                sorted = sortiebucks(ib);
+                *base = (u64int)ib->chunks * ib->size;
+                if(sorted != clumps){
+                        fprint(2, "sorting messed up: clumps=%lld sorted=%lld\n", clumps, sorted);
+                        ok = -1;
+                }
+        }
+        freeiebucks(ib);
+        if(ok < 0)
+                return TWID64;
+        return clumps;
+}
+
+#define CHECK(cis)        if(((ulong*)cis)[-4] != 0xA110C09) xabort();
+
+void
+xabort(void)
+{
+        int *x;
+
+        x = 0;
+        *x = 0;
+}
+
+/*
+ * read in all of the arena's clump directory,
+ * convert to IEntry format, and bucket sort based
+ * on the first few bits.
+ */
+static u32int
+readarenainfo(IEBucks *ib, Arena *arena, u64int a, Bloom *b)
+{
+        IEntry ie;
+        ClumpInfo *ci, *cis;
+        u32int clump;
+        int i, n, ok, nskip;
+//        static Biobuf bout;
+
+//ZZZ remove fprint?
+//fprint(2, "ra %s %d %d\n", arena->name, arena->memstats.clumps, arena->diskstats.clumps);
+        if(arena->memstats.clumps)
+                fprint(2, "\tarena %s: %d entries\n", arena->name, arena->memstats.clumps);
+        else
+                fprint(2, "[%s] ", arena->name);
+
+        cis = MKN(ClumpInfo, ClumpChunks);
+        ok = 0;
+        nskip = 0;
+        memset(&ie, 0, sizeof(IEntry));
+//        Binit(&bout, 1, OWRITE);
+        for(clump = 0; clump < arena->memstats.clumps; clump += n){
+                n = ClumpChunks;
+                if(n > arena->memstats.clumps - clump)
+                        n = arena->memstats.clumps - clump;
+                if(readclumpinfos(arena, clump, cis, n) != n){
+                        seterr(EOk, "arena directory read failed: %r");
+                        ok = -1;
+                        break;
+                }
+
+                for(i = 0; i < n; i++){
+                        ci = &cis[i];
+                        ie.ia.type = ci->type;
+                        ie.ia.size = ci->uncsize;
+                        ie.ia.addr = a;
+                        a += ci->size + ClumpSize;
+                        ie.ia.blocks = (ci->size + ClumpSize + (1 << ABlockLog) - 1) >> ABlockLog;
+                        scorecp(ie.score, ci->score);
+                //        Bprint(&bout, "%22lld %V %3d %5d\n",
+                //                ie.ia.addr, ie.score, ie.ia.type, ie.ia.size);
+                        if(ci->type == VtCorruptType){
+                        //        print("! %V %22lld %3d %5d %3d\n",
+                        //                ie.score, ie.ia.addr, ie.ia.type, ie.ia.size, ie.ia.blocks);
+                                nskip++;
+                        }else
+                                sprayientry(ib, &ie);
+                        markbloomfilter(b, ie.score);
+                }
+        }
+//        Bterm(&bout);
+        free(cis);
+        if(ok < 0)
+                return TWID32;
+        return clump - nskip;
+}
+
+/*
+ * initialize the external bucket sorting data structures
+ */
+static IEBucks*
+initiebucks(Part *part, int bits, u32int size)
+{
+        IEBucks *ib;
+        int i;
+
+        ib = MKZ(IEBucks);
+        if(ib == nil){
+                seterr(EOk, "out of memory");
+                return nil;
+        }
+        ib->bits = bits;
+        ib->nbucks = 1 << bits;
+        ib->size = size;
+        ib->usable = (size - U32Size) / IEntrySize * IEntrySize;
+        ib->bucks = MKNZ(IEBuck, ib->nbucks);
+        if(ib->bucks == nil){
+                seterr(EOk, "out of memory allocation sorting buckets");
+                freeiebucks(ib);
+                return nil;
+        }
+        ib->xbuf = MKN(u8int, size * ((1 << bits)+1));
+        ib->buf = (u8int*)(((ulong)ib->xbuf+size-1)&~(ulong)(size-1));
+        if(ib->buf == nil){
+                seterr(EOk, "out of memory allocating sorting buckets' buffers");
+                freeiebucks(ib);
+                return nil;
+        }
+        for(i = 0; i < ib->nbucks; i++){
+                ib->bucks[i].head = TWID32;
+                ib->bucks[i].buf = &ib->buf[i * size];
+        }
+        ib->part = part;
+        return ib;
+}
+
+static void
+freeiebucks(IEBucks *ib)
+{
+        if(ib == nil)
+                return;
+        free(ib->bucks);
+        free(ib->buf);
+        free(ib);
+}
+
+/*
+ * initial sort: put the entry into the correct bucket
+ */
+static int
+sprayientry(IEBucks *ib, IEntry *ie)
+{
+        u32int n;
+        int b;
+
+        b = hashbits(ie->score, ib->bits);
+        n = ib->bucks[b].used;
+        if(n + IEntrySize > ib->usable){
+                /* should be flushed below, but if flush fails, this can happen */
+                seterr(EOk, "out of space in bucket");
+                return -1;
+        }
+        packientry(ie, &ib->bucks[b].buf[n]);
+        n += IEntrySize;
+        ib->bucks[b].used = n;
+        if(n + IEntrySize <= ib->usable)
+                return 0;
+        return flushiebuck(ib, b, 1);
+}
+
+/*
+ * finish sorting:
+ * for each bucket, read it in and sort it
+ * write out the the final file
+ */
+static u64int
+sortiebucks(IEBucks *ib)
+{
+        u64int tot;
+        u32int n;
+        int i;
+
+        if(flushiebucks(ib) < 0)
+                return TWID64;
+        for(i = 0; i < ib->nbucks; i++)
+                ib->bucks[i].buf = nil;
+        ib->off = (u64int)ib->chunks * ib->size;
+        free(ib->xbuf);
+if(0){
+        fprint(2, "ib->max = %lld\n", ib->max);
+        fprint(2, "ib->chunks = %ud\n", ib->chunks);
+}
+        ib->buf = MKN(u8int, ib->max + U32Size);
+        if(ib->buf == nil){
+                seterr(EOk, "out of memory allocating final sorting buffer; try more buckets");
+                return TWID64;
+        }
+        tot = 0;
+        for(i = 0; i < ib->nbucks; i++){
+                n = sortiebuck(ib, i);
+                if(n == TWID32)
+                        return TWID64;
+                if(n != ib->bucks[i].total/IEntrySize)
+                        fprint(2, "bucket %d changed count %d => %d\n", 
+                                i, (int)(ib->bucks[i].total/IEntrySize), n);
+                tot += n;
+        }
+        return tot;
+        return 0;
+}
+
+/*
+ * sort from bucket b of ib into the output file to
+ */
+static u32int
+sortiebuck(IEBucks *ib, int b)
+{
+        u32int n;
+
+        n = readiebuck(ib, b);
+        if(n == TWID32)
+                return TWID32;
+        qsort(ib->buf, n, IEntrySize, ientrycmp);
+        if(writepart(ib->part, ib->off, ib->buf, n * IEntrySize) < 0){
+                seterr(EOk, "can't write sorted bucket: %r");
+                return TWID32;
+        }
+        ib->off += n * IEntrySize;
+        return n;
+}
+
+/*
+ * write out a single bucket
+ */
+static int
+flushiebuck(IEBucks *ib, int b, int reset)
+{
+        u32int n;
+
+        if(ib->bucks[b].used == 0)
+                return 0;
+        n = ib->bucks[b].used;
+        U32PUT(&ib->bucks[b].buf[n], ib->bucks[b].head);
+        n += U32Size;
+        USED(n);
+        if(writepart(ib->part, (u64int)ib->chunks * ib->size, ib->bucks[b].buf, ib->size) < 0){
+                seterr(EOk, "can't write sorting bucket to file: %r");
+xabort();
+                return -1;
+        }
+        ib->bucks[b].head = ib->chunks++;
+        ib->bucks[b].total += ib->bucks[b].used;
+        if(reset)
+                ib->bucks[b].used = 0;
+        return 0;
+}
+
+/*
+ * write out all of the buckets, and compute
+ * the maximum size of any bucket
+ */
+static int
+flushiebucks(IEBucks *ib)
+{
+        int i;
+
+        for(i = 0; i < ib->nbucks; i++){
+                if(flushiebuck(ib, i, 0) < 0)
+                        return -1;
+                if(ib->bucks[i].total > ib->max)
+                        ib->max = ib->bucks[i].total;
+        }
+        return 0;
+}
+
+/*
+ * read in the chained buffers for bucket b,
+ * and return it's total number of IEntries
+ */
+static u32int
+readiebuck(IEBucks *ib, int b)
+{
+        u32int head, m, n;
+
+        head = ib->bucks[b].head;
+        n = 0;
+        m = ib->bucks[b].used;
+        if(m == 0)
+                m = ib->usable;
+//        if(ib->bucks[b].total)
+//                fprint(2, "\tbucket %d: %d entries\n", b, ib->bucks[b].total/IEntrySize);
+        while(head != TWID32){
+                if(readpart(ib->part, (u64int)head * ib->size, &ib->buf[n], m + U32Size) < 0){
+                        seterr(EOk, "can't read index sort bucket: %r");
+                        return TWID32;
+                }
+                n += m;
+                head = U32GET(&ib->buf[n]);
+                m = ib->usable;
+        }
+        if(n != ib->bucks[b].total)
+                fprint(2, "\tbucket %d: expected %d entries, got %d\n",
+                        b, (int)ib->bucks[b].total/IEntrySize, n/IEntrySize);
+        return n / IEntrySize;
+}
diff --git a/src/cmd/venti/srv/stats.c b/src/cmd/venti/srv/stats.c
t@@ -0,0 +1,212 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+int collectstats = 1;
+
+/* keep in sync with dat.h:/NStat */
+Statdesc statdesc[NStat] =
+{
+        { "rpc total", },
+        { "rpc reads", },
+        { "rpc reads ok", },
+        { "rpc reads failed", },
+        { "rpc read bytes", },
+        { "rpc read time", },
+        { "rpc read cached", },
+        { "rpc read cached time", },
+        { "rpc read uncached", },
+        { "rpc read uncached time "},
+        
+        { "rpc writes", },
+        { "rpc writes new", },
+        { "rpc writes old", },
+        { "rpc writes failed", },
+        { "rpc write bytes", },
+        { "rpc write time", },
+        { "rpc write new time", },
+        { "rpc write old time", },
+
+        { "lump cache hits", },
+        { "lump cache misses", },
+        { "lump cache reads", },
+        { "lump cache writes", },
+        { "lump cache size", },
+        { "lump cache stall", },
+        { "lump cache read time", },
+
+        { "disk cache hits", },
+        { "disk cache misses", },
+        { "disk cache lookups", },
+        { "disk cache reads", },
+        { "disk cache writes", },
+        { "disk cache dirty", },
+        { "disk cache size", },
+        { "disk cache flushes", },
+        { "disk cache stalls", },
+        { "disk cache lookup time", },
+
+        { "disk block stalls", },
+        { "lump stalls", },
+
+        { "index cache hits", },
+        { "index cache misses", },
+        { "index cache reads", },
+        { "index cache writes", },
+        { "index cache fills", },
+        { "index cache prefetches", },
+        { "index cache dirty", },
+        { "index cache size", },
+        { "index cache flushes", },
+        { "index cache stalls", },
+        { "index cache read time", },
+
+        { "bloom filter hits", },
+        { "bloom filter misses", },
+        { "bloom filter false misses", },
+        { "bloom filter lookups", },
+        { "bloom filter ones", },
+        { "bloom filter bits", },
+        { "bloom filter lookup time", },
+
+        { "arena block reads", },
+        { "arena block read bytes", },
+        { "arena block writes", },
+        { "arena block write bytes", },
+
+        { "isect block reads", },
+        { "isect block read bytes", },
+        { "isect block writes", },
+        { "isect block write bytes", },
+
+        { "sum reads", },
+        { "sum read bytes", },
+};
+
+QLock statslock;
+Stats stats;
+Stats *stathist;
+int nstathist;
+ulong statind;
+ulong stattime;
+
+void
+statsproc(void *v)
+{
+        USED(v);
+
+        for(;;){
+                stats.now = time(0);
+                stathist[stattime%nstathist] = stats;
+                stattime++;
+                sleep(1000);
+        }
+}
+
+void
+statsinit(void)
+{
+        nstathist = 90000;
+        stathist = MKNZ(Stats, nstathist);
+        vtproc(statsproc, nil);
+}
+
+void
+setstat(int index, long val)
+{
+        qlock(&statslock);
+        stats.n[index] = val;
+        qunlock(&statslock);
+}
+
+void
+addstat(int index, int inc)
+{
+        if(!collectstats)
+                return;
+        qlock(&statslock);
+        stats.n[index] += inc;
+        qunlock(&statslock);
+}
+
+void
+addstat2(int index, int inc, int index1, int inc1)
+{
+        if(!collectstats)
+                return;
+        qlock(&statslock);
+        stats.n[index] += inc;
+        stats.n[index1] += inc1;
+        qunlock(&statslock);
+}
+
+void
+printstats(void)
+{
+}
+
+void
+binstats(long (*fn)(Stats *s0, Stats *s1, void *arg), void *arg,
+        long t0, long t1, Statbin *bin, int nbin)
+{
+        long t, xt0, te, v;
+        int i, j, lo, hi, m, oj;
+        vlong tot;
+        Statbin *b;
+        
+        t = stats.now;
+        
+        /* negative times mean relative to now. */
+        if(t0 <= 0)
+                t0 += t;
+        if(t1 <= 0)
+                t1 += t;
+        /* ten minute range if none given */
+        if(t1 <= t0)
+                t0 = t1 - 60*10;
+        if(0) fprint(2, "stats %ld-%ld\n", t0, t1);
+        
+        /* binary search to find t0-1 or close */
+        lo = stattime;
+        hi = stattime+nstathist;
+        while(lo+1 < hi){
+                m = (lo+hi)/2;
+                if(stathist[m%nstathist].now >= t0)
+                        hi = m;
+                else
+                        lo = m;
+        }
+        xt0 = stathist[lo%nstathist].now;
+        if(0) fprint(2, "bsearch found %ld\n", xt0);
+        if(xt0 >= t1){
+                /* no samples */
+                memset(bin, 0, nbin*sizeof bin[0]);
+                return;
+        }
+
+        hi = stattime+nstathist;
+        te = t0;
+        j = lo+1;
+        for(i=0; insamp==0 || v < b->min)
+                                b->min = v;
+                        if(b->nsamp==0 || v > b->max)
+                                b->max = v;
+                        tot += v;
+                        b->nsamp++;
+                }
+                if(0) fprint(2, "bin%d: %ld to %ld; %d to %d - %d samples\n", i, t, te, oj, j, b->nsamp);
+                if(b->nsamp)
+                        b->avg = tot / b->nsamp;
+                if(b->nsamp==0 && i>0)
+                        *b = bin[i-1];
+        }        
+}
diff --git a/src/cmd/venti/srv/stdinc.h b/src/cmd/venti/srv/stdinc.h
t@@ -0,0 +1,9 @@
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
diff --git a/src/cmd/venti/srv/syncarena.c b/src/cmd/venti/srv/syncarena.c
t@@ -0,0 +1,174 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+static int        writeclumphead(Arena *arena, u64int aa, Clump *cl);
+static int        writeclumpmagic(Arena *arena, u64int aa, u32int magic);
+
+int
+clumpinfocmp(ClumpInfo *c, ClumpInfo *d)
+{
+        return c->type != d->type
+                || c->size != d->size
+                || c->uncsize != d->uncsize
+                || scorecmp(c->score, d->score)!=0;
+}
+
+/*
+ * synchronize the clump info directory with
+ * with the clumps actually stored in the arena.
+ * the directory should be at least as up to date
+ * as the arena's trailer.
+ *
+ * checks/updates at most n clumps.
+ *
+ * returns 0 if ok, flags if error occurred
+ */
+int
+syncarena(Arena *arena, u64int start, u32int n, int zok, int fix)
+{
+        ZBlock *lump;
+        Clump cl;
+        ClumpInfo ci;
+        static ClumpInfo zci = { .type = -1 };
+        u8int score[VtScoreSize];
+        u64int uncsize, used, aa;
+        u32int clump, clumps, cclumps, magic;
+        int err, flush, broken;
+        AState as;
+
+        used = arena->memstats.used;
+        clumps = arena->memstats.clumps;
+        cclumps = arena->memstats.cclumps;
+        uncsize = arena->memstats.uncsize;
+        trace(TraceProc, "syncarena start");
+        flush = 0;
+        err = 0;
+        for(; n; n--){
+                aa = arena->memstats.used;
+                clump = arena->memstats.clumps;
+                magic = clumpmagic(arena, aa);
+                if(magic == ClumpFreeMagic)
+                        break;
+                if(magic != arena->clumpmagic){
+                        fprint(2, "%s: illegal clump magic number=%#8.8ux at clump=%d\n", arena->name, magic, clump);
+                        /* err |= SyncDataErr; */
+                        if(fix && writeclumpmagic(arena, aa, ClumpFreeMagic) < 0){
+                                fprint(2, "can't write corrected clump free magic: %r");
+                                err |= SyncFixErr;
+                        }
+                        break;
+                }
+
+                broken = 0;
+                lump = loadclump(arena, aa, 0, &cl, score, 0);
+                if(lump == nil){
+                        fprint(2, "%s: clump=%d failed to read correctly: %r\n", arena->name, clump);
+                        break;
+                        err |= SyncDataErr;
+                }else if(cl.info.type != VtCorruptType){
+                        scoremem(score, lump->data, cl.info.uncsize);
+                        if(scorecmp(cl.info.score, score) != 0){
+                                /* ignore partially written block */
+                                if(cl.encoding == ClumpENone)
+                                        break;
+                                fprint(2, "%s: clump=%d has mismatched score\n", arena->name, clump);
+                                err |= SyncDataErr;
+                                broken = 1;
+                        }else if(vttypevalid(cl.info.type) < 0){
+                                fprint(2, "%s: clump=%d has invalid type %d", arena->name, clump, cl.info.type);
+                                err |= SyncDataErr;
+                                broken = 1;
+                        }
+                        if(broken && fix){
+                                cl.info.type = VtCorruptType;
+                                if(writeclumphead(arena, aa, &cl) < 0){
+                                        fprint(2, "%s: can't write corrected clump header: %r", arena->name);
+                                        err |= SyncFixErr;
+                                }
+                        }
+                }
+                freezblock(lump);
+                arena->memstats.used += ClumpSize + cl.info.size;
+
+                arena->memstats.clumps++;
+                if(!broken && readclumpinfo(arena, clump, &ci)<0){
+                        fprint(2, "%s: arena directory read failed\n", arena->name);
+                        broken = 1;
+                }else if(!broken && clumpinfocmp(&ci, &cl.info)!=0){
+                        if(clumpinfocmp(&ci, &zci) == 0){
+                                err |= SyncCIZero;
+                                if(!zok)
+                                        fprint(2, "%s: unwritten clump info for clump=%d\n", arena->name, clump);
+                        }else{
+                                err |= SyncCIErr;
+                                fprint(2, "%s: bad clump info for clump=%d\n", arena->name, clump);
+                                fprint(2, "\texpected score=%V type=%d size=%d uncsize=%d\n",
+                                        cl.info.score, cl.info.type, cl.info.size, cl.info.uncsize);
+                                fprint(2, "\tfound score=%V type=%d size=%d uncsize=%d\n",
+                                        ci.score, ci.type, ci.size, ci.uncsize);
+                        }
+                        broken = 1;
+                }
+                if(broken && fix){
+                        flush = 1;
+                        ci = cl.info;
+                        if(writeclumpinfo(arena, clump, &ci) < 0){
+                                fprint(2, "%s: can't write correct clump directory: %r\n", arena->name);
+                                err |= SyncFixErr;
+                        }
+                }
+                trace(TraceProc, "syncarena unindexed clump %V %d", cl.info.score, arena->memstats.clumps);
+
+                arena->memstats.uncsize += cl.info.uncsize;
+                if(cl.info.size < cl.info.uncsize)
+                        arena->memstats.cclumps++;
+        }
+
+        if(flush){
+                trace(TraceProc, "syncarena flush");
+                arena->wtime = now();
+                if(arena->ctime == 0 && arena->memstats.clumps)
+                        arena->ctime = arena->wtime;
+                flushdcache();
+        }
+
+        if(used != arena->memstats.used
+        || clumps != arena->memstats.clumps
+        || cclumps != arena->memstats.cclumps
+        || uncsize != arena->memstats.uncsize)
+                err |= SyncHeader;
+        if(start && (err&SyncHeader)){
+                trace(TraceProc, "syncarena setdcachestate");
+                as.arena = arena;
+                as.aa = start+arena->memstats.used;
+                as.stats = arena->memstats;
+                setdcachestate(&as);
+        }
+
+        return err;
+}
+
+static int
+writeclumphead(Arena *arena, u64int aa, Clump *cl)
+{
+        ZBlock *zb;
+        int bad;
+
+        zb = alloczblock(ClumpSize, 0, arena->blocksize);
+        if(zb == nil)
+                return -1;
+        bad = packclump(cl, zb->data, arena->clumpmagic)<0
+                || writearena(arena, aa, zb->data, ClumpSize) != ClumpSize;
+        freezblock(zb);
+        return bad ? -1 : 0;
+}
+
+static int
+writeclumpmagic(Arena *arena, u64int aa, u32int magic)
+{
+        u8int buf[U32Size];
+
+        packmagic(magic, buf);
+        return writearena(arena, aa, buf, U32Size) == U32Size;
+}
diff --git a/src/cmd/venti/srv/syncindex.c b/src/cmd/venti/srv/syncindex.c
t@@ -0,0 +1,73 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+static        int        verbose;
+void
+usage(void)
+{
+        fprint(2, "usage: syncindex [-fv] [-B blockcachesize] config\n");
+        threadexitsall("usage");
+}
+
+Config conf;
+
+void
+threadmain(int argc, char *argv[])
+{
+        u32int bcmem, icmem;
+        int fix;
+
+        fix = 0;
+        bcmem = 0;
+        icmem = 0;
+        ARGBEGIN{
+        case 'B':
+                bcmem = unittoull(EARGF(usage()));
+                break;
+        case 'I':
+                icmem = unittoull(EARGF(usage()));
+                break;
+        case 'f':
+                fix++;
+                break;
+        case 'v':
+                verbose++;
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        if(!fix)
+                readonly = 1;
+
+        if(argc != 1)
+                usage();
+
+        if(initventi(argv[0], &conf) < 0)
+                sysfatal("can't init venti: %r");
+
+        if(bcmem < maxblocksize * (mainindex->narenas + mainindex->nsects * 4 + 16))
+                bcmem = maxblocksize * (mainindex->narenas + mainindex->nsects * 4 + 16);
+        if(0) fprint(2, "initialize %d bytes of disk block cache\n", bcmem);
+        initdcache(bcmem);
+        initlumpcache(1*1024*1024, 1024/8);
+        icmem = u64log2(icmem / (sizeof(IEntry)+sizeof(IEntry*)) / ICacheDepth);
+        if(icmem < 4)
+                icmem = 4;
+        if(1) fprint(2, "initialize %d bytes of index cache for %d index entries\n",
+                (sizeof(IEntry)+sizeof(IEntry*)) * (1 << icmem) * ICacheDepth,
+                (1 << icmem) * ICacheDepth);
+        initicache(icmem, ICacheDepth);
+        initicachewrite();
+        if(mainindex->bloom)
+                startbloomproc(mainindex->bloom);
+
+        if(verbose)
+                printindex(2, mainindex);
+        if(syncindex(mainindex, fix, 1, 0) < 0)
+                sysfatal("failed to sync index=%s: %r\n", mainindex->name);
+
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/srv/syncindex0.c b/src/cmd/venti/srv/syncindex0.c
t@@ -0,0 +1,167 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+enum
+{
+        ClumpChunks        = 32*1024
+};
+
+static int missing, wrong;
+
+/*
+ * shell sort is plenty good enough
+ * because we're going to do a bunch of disk i/o's
+ */
+static void
+sortclumpinfo(ClumpInfo *ci, int *s, int n)
+{
+        int i, j, m, t;
+
+        for(m = (n + 3) / 5; m > 0; m = (m + 1) / 3){
+                for(i = n - m; i-- > 0;){
+                        for(j = i + m; j < n; j += m){
+                                if(memcmp(ci[s[j - m]].score, ci[s[j]].score, VtScoreSize) <= 0)
+                                        break;
+                                t = s[j];
+                                s[j] = s[j - m];
+                                s[j - m] = t;
+                        }
+                }
+        }
+}
+
+int
+syncarenaindex(Index *ix, Arena *arena, u32int clump, u64int a, int fix, int *pflush, int check)
+{
+        Packet *pack;
+        IEntry ie;
+        IAddr ia;
+        ClumpInfo *ci, *cis;
+        u64int *addrs;
+        int i, n, ok, *s, flush;
+
+        trace(TraceProc, "syncarenaindex enter");
+
+        flush = 0;
+        cis = MKN(ClumpInfo, ClumpChunks);
+        addrs = MKN(u64int, ClumpChunks);
+        s = MKN(int, ClumpChunks);
+        ok = 0;
+        for(; clump < arena->memstats.clumps; clump += n){
+                n = ClumpChunks;
+                if(n > arena->memstats.clumps - clump)
+                        n = arena->memstats.clumps - clump;
+                n = readclumpinfos(arena, clump, cis, n);
+                if(n <= 0){
+                        fprint(2, "arena directory read failed\n");
+                        ok = -1;
+                        break;
+                }
+
+                for(i = 0; i < n; i++){
+                        addrs[i] = a;
+                        a += cis[i].size + ClumpSize;
+                        s[i] = i;
+                }
+
+                sortclumpinfo(cis, s, n);
+
+                for(i = 0; i < n; i++){
+                        ci = &cis[s[i]];
+                        ia.type = ci->type;
+                        ia.size = ci->uncsize;
+                        ia.addr = addrs[s[i]];
+                        ia.blocks = (ci->size + ClumpSize + (1 << ABlockLog) - 1) >> ABlockLog;
+
+                        if(!check)
+                                goto Add;
+                        if(loadientry(ix, ci->score, ci->type, &ie) < 0){
+                                trace(TraceProc, "syncarenaindex missing block %V.%d", ci->score, ci->type);
+                                missing++;
+                        if(0)        fprint(2, "missing block type=%d score=%V\n", ci->type, ci->score);
+                        }else if(iaddrcmp(&ia, &ie.ia) != 0){
+                                trace(TraceProc, "syncarenaindex mismatched entry");
+                                fprint(2, "\nmismatched index entry and clump at %d\n", clump + i);
+                                fprint(2, "\tclump: type=%d size=%d blocks=%d addr=%lld\n", ia.type, ia.size, ia.blocks, ia.addr);
+                                fprint(2, "\tindex: type=%d size=%d block=%d addr=%lld\n", ie.ia.type, ie.ia.size, ie.ia.blocks, ie.ia.addr);
+                                pack = readlump(ie.score, ie.ia.type, ie.ia.size, nil);
+                                packetfree(pack);
+                                if(pack != nil){
+                                        fprint(2, "duplicated lump\n");
+                                        continue;
+                                }
+                                wrong++;
+                        }else
+                                continue;
+                Add:
+                        if(!fix){
+                                ok = -1;
+                                continue;
+                        }
+                        flush = 1;
+                        trace(TraceProc, "syncarenaindex insert %V", ci->score);
+                        insertscore(ci->score, &ia, 1);
+                }
+
+                if(0 && clump / 1000 != (clump + n) / 1000)
+                        fprint(2, ".");
+        }
+        free(cis);
+        free(addrs);
+        free(s);
+        if(flush){
+                flushdcache();
+                *pflush = 1;
+        }
+        return ok;
+}
+
+int
+syncindex(Index *ix, int fix, int mustflush, int check)
+{
+        Arena *arena;
+        u64int a;
+        u32int clump;
+        int i, e, e1, ok, ok1, flush;
+
+        ok = 0;
+        flush = 0;
+        for(i = 0; i < ix->narenas; i++){
+                trace(TraceProc, "syncindex start %d", i);
+                arena = ix->arenas[i];
+                clump = arena->memstats.clumps;
+                a = arena->memstats.used;
+                e = syncarena(arena, ix->amap[i].start, TWID32, fix, fix);
+                e1 = e;
+                if(fix)
+                        e1 &= ~(SyncHeader|SyncCIZero|SyncCIErr);
+                if(e1 == SyncHeader)
+                        fprint(2, "arena %s: header is out-of-date\n", arena->name);
+                if(e1)
+                        ok = -1;
+                else{
+                        ok1 = syncarenaindex(ix, arena, clump, a + ix->amap[i].start, fix, &flush, check);
+                        if(ok1 < 0)
+                                fprint(2, "syncarenaindex: %r\n");
+                        if(fix && ok1==0 && (e & SyncHeader) && wbarena(arena) < 0)
+                                fprint(2, "arena=%s header write failed: %r\n", arena->name);
+                        ok |= ok1;
+                }
+        }
+        if(missing || wrong)
+                fprint(2, "syncindex: %d missing entries, %d wrong entries (flush=%d)\n", missing, wrong, flush);
+        if(fix && wbindex(ix) < 0){
+                fprint(2, "can't write back index header for %s: %r\n", ix->name);
+                return -1;
+        }
+        if(fix && flush){
+                flushdcache();
+                if(mustflush){
+                        flushicache();
+                        flushdcache();
+                }else
+                        kickicache();
+        }
+        return ok;
+}
diff --git a/src/cmd/venti/srv/trace.c b/src/cmd/venti/srv/trace.c
t@@ -0,0 +1,38 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+char TraceDisk[] = "disk";
+char TraceLump[] = "lump";
+char TraceBlock[] = "block";
+char TraceProc[] = "proc";
+char TraceWork[] = "work";
+char TraceQuiet[] = "quiet";
+char TraceRpc[] = "rpc";
+
+void
+trace(char *level, char *fmt, ...)
+{
+        char buf[512];
+        va_list arg;
+
+        if(level == nil || !ventilogging)
+                return;
+        va_start(arg, fmt);
+        vsnprint(buf, sizeof buf, fmt, arg);
+        va_end(arg);
+        vtlog(level, "%T %s: %s
\n", + threadgetname(), buf); + vtlog("all", "%T %s %s: %s
\n", + level, threadgetname(), buf); +} + +void +traceinit(void) +{ +} + +void +settrace(char *trace) +{ +}
diff --git a/src/cmd/venti/srv/unittoull.c b/src/cmd/venti/srv/unittoull.c
t@@ -0,0 +1,30 @@
+#include "stdinc.h"
+
+#define TWID64        ((u64int)~(u64int)0)
+
+u64int
+unittoull(char *s)
+{
+        char *es;
+        u64int n;
+
+        if(s == nil)
+                return TWID64;
+        n = strtoul(s, &es, 0);
+        if(*es == 'k' || *es == 'K'){
+                n *= 1024;
+                es++;
+        }else if(*es == 'm' || *es == 'M'){
+                n *= 1024*1024;
+                es++;
+        }else if(*es == 'g' || *es == 'G'){
+                n *= 1024*1024*1024;
+                es++;
+        }else if(*es == 't' || *es == 'T'){
+                n *= 1024*1024;
+                n *= 1024*1024;
+        }
+        if(*es != '\0')
+                return TWID64;
+        return n;
+}
diff --git a/src/cmd/venti/srv/unwhack.c b/src/cmd/venti/srv/unwhack.c
t@@ -0,0 +1,179 @@
+#include "stdinc.h"
+#include "whack.h"
+
+enum
+{
+        DMaxFastLen        = 7,
+        DBigLenCode        = 0x3c,                /* minimum code for large lenth encoding */
+        DBigLenBits        = 6,
+        DBigLenBase        = 1                /* starting items to encode for big lens */
+};
+
+static uchar lenval[1 << (DBigLenBits - 1)] =
+{
+        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+        3, 3, 3, 3, 3, 3, 3, 3,
+        4, 4, 4, 4,
+        5,
+        6,
+        255,
+        255
+};
+
+static uchar lenbits[] =
+{
+        0, 0, 0,
+        2, 3, 5, 5,
+};
+
+static uchar offbits[16] =
+{
+        5, 5, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 12, 13
+};
+
+static ushort offbase[16] =
+{
+        0, 0x20,
+        0x40, 0x60,
+        0x80, 0xc0,
+        0x100, 0x180,
+        0x200, 0x300,
+        0x400, 0x600,
+        0x800, 0xc00,
+        0x1000,
+        0x2000
+};
+
+void
+unwhackinit(Unwhack *uw)
+{
+        uw->err[0] = '\0';
+}
+
+int
+unwhack(Unwhack *uw, uchar *dst, int ndst, uchar *src, int nsrc)
+{
+        uchar *s, *d, *dmax, *smax, lit;
+        ulong uwbits, lithist;
+        int i, off, len, bits, use, code, uwnbits, overbits;
+
+        d = dst;
+        dmax = d + ndst;
+
+        smax = src + nsrc;
+        uwnbits = 0;
+        uwbits = 0;
+        overbits = 0;
+        lithist = ~0;
+        while(src < smax || uwnbits - overbits >= MinDecode){
+                while(uwnbits <= 24){
+                        uwbits <<= 8;
+                        if(src < smax)
+                                uwbits |= *src++;
+                        else
+                                overbits += 8;
+                        uwnbits += 8;
+                }
+
+                /*
+                 * literal
+                 */
+                len = lenval[(uwbits >> (uwnbits - 5)) & 0x1f];
+                if(len == 0){
+                        if(lithist & 0xf){
+                                uwnbits -= 9;
+                                lit = (uwbits >> uwnbits) & 0xff;
+                                lit &= 255;
+                        }else{
+                                uwnbits -= 8;
+                                lit = (uwbits >> uwnbits) & 0x7f;
+                                if(lit < 32){
+                                        if(lit < 24){
+                                                uwnbits -= 2;
+                                                lit = (lit << 2) | ((uwbits >> uwnbits) & 3);
+                                        }else{
+                                                uwnbits -= 3;
+                                                lit = (lit << 3) | ((uwbits >> uwnbits) & 7);
+                                        }
+                                        lit = (lit - 64) & 0xff;
+                                }
+                        }
+                        if(d >= dmax){
+                                snprint(uw->err, WhackErrLen, "too much output");
+                                return -1;
+                        }
+                        *d++ = lit;
+                        lithist = (lithist << 1) | (lit < 32) | (lit > 127);
+                        continue;
+                }
+
+                /*
+                 * length
+                 */
+                if(len < 255)
+                        uwnbits -= lenbits[len];
+                else{
+                        uwnbits -= DBigLenBits;
+                        code = ((uwbits >> uwnbits) & ((1 << DBigLenBits) - 1)) - DBigLenCode;
+                        len = DMaxFastLen;
+                        use = DBigLenBase;
+                        bits = (DBigLenBits & 1) ^ 1;
+                        while(code >= use){
+                                len += use;
+                                code -= use;
+                                code <<= 1;
+                                uwnbits--;
+                                if(uwnbits < 0){
+                                        snprint(uw->err, WhackErrLen, "len out of range");
+                                        return -1;
+                                }
+                                code |= (uwbits >> uwnbits) & 1;
+                                use <<= bits;
+                                bits ^= 1;
+                        }
+                        len += code;
+
+                        while(uwnbits <= 24){
+                                uwbits <<= 8;
+                                if(src < smax)
+                                        uwbits |= *src++;
+                                else
+                                        overbits += 8;
+                                uwnbits += 8;
+                        }
+                }
+
+                /*
+                 * offset
+                 */
+                uwnbits -= 4;
+                bits = (uwbits >> uwnbits) & 0xf;
+                off = offbase[bits];
+                bits = offbits[bits];
+
+                uwnbits -= bits;
+                off |= (uwbits >> uwnbits) & ((1 << bits) - 1);
+                off++;
+
+                if(off > d - dst){
+                        snprint(uw->err, WhackErrLen, "offset out of range: off=%d d=%ld len=%d nbits=%d", off, d - dst, len, uwnbits);
+                        return -1;
+                }
+                if(d + len > dmax){
+                        snprint(uw->err, WhackErrLen, "len out of range");
+                        return -1;
+                }
+                s = d - off;
+                for(i = 0; i < len; i++)
+                        d[i] = s[i];
+                d += len;
+        }
+        if(uwnbits < overbits){
+                snprint(uw->err, WhackErrLen, "compressed data overrun");
+                return -1;
+        }
+
+        len = d - dst;
+
+        return len;
+}
diff --git a/src/cmd/venti/srv/utils.c b/src/cmd/venti/srv/utils.c
t@@ -0,0 +1,252 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+int
+namecmp(char *s, char *t)
+{
+        return strncmp(s, t, ANameSize);
+}
+
+void
+namecp(char *dst, char *src)
+{
+        strncpy(dst, src, ANameSize - 1);
+        dst[ANameSize - 1] = '\0';
+}
+
+int
+nameok(char *name)
+{
+        char *t;
+        int c;
+
+        if(name == nil)
+                return -1;
+        for(t = name; c = *t; t++)
+                if(t - name >= ANameSize
+                || c < ' ' || c >= 0x7f)
+                        return -1;
+        return 0;
+}
+
+int
+stru32int(char *s, u32int *r)
+{
+        char *t;
+        u32int n, nn, m;
+        int c;
+
+        m = TWID32 / 10;
+        n = 0;
+        for(t = s; ; t++){
+                c = *t;
+                if(c < '0' || c > '9')
+                        break;
+                if(n > m)
+                        return -1;
+                nn = n * 10 + c - '0';
+                if(nn < n)
+                        return -1;
+                n = nn;
+        }
+        *r = n;
+        return s != t && *t == '\0';
+}
+
+int
+stru64int(char *s, u64int *r)
+{
+        char *t;
+        u64int n, nn, m;
+        int c;
+
+        m = TWID64 / 10;
+        n = 0;
+        for(t = s; ; t++){
+                c = *t;
+                if(c < '0' || c > '9')
+                        break;
+                if(n > m)
+                        return -1;
+                nn = n * 10 + c - '0';
+                if(nn < n)
+                        return -1;
+                n = nn;
+        }
+        *r = n;
+        return s != t && *t == '\0';
+}
+
+int
+vttypevalid(int type)
+{
+        return type < VtMaxType;
+}
+
+static char*
+logit(int severity, char *fmt, va_list args)
+{
+        char *s;
+
+        s = vsmprint(fmt, args);
+        if(s == nil)
+                return nil;
+        if(argv0 == nil)
+                fprint(2, "%s: err %d: %s\n", argv0, severity, s);
+        else
+                fprint(2, "err %d: %s\n", severity, s);
+        return s;
+}
+
+void
+seterr(int severity, char *fmt, ...)
+{
+        char *s;
+        va_list args;
+
+        va_start(args, fmt);
+        s = logit(severity, fmt, args);
+        va_end(args);
+        if(s == nil)
+                werrstr("error setting error");
+        else{
+                werrstr("%s", s);
+                free(s);
+        }
+}
+
+void
+logerr(int severity, char *fmt, ...)
+{
+        char *s;
+        va_list args;
+
+        va_start(args, fmt);
+        s = logit(severity, fmt, args);
+        va_end(args);
+        free(s);
+}
+
+u32int
+now(void)
+{
+        return time(nil);
+}
+
+int abortonmem = 1;
+
+void *
+emalloc(ulong n)
+{
+        void *p;
+
+        p = malloc(n);
+        if(p == nil){
+                if(abortonmem)
+                        abort();
+                sysfatal("out of memory allocating %lud", n);
+        }
+        memset(p, 0xa5, n);
+if(0)print("emalloc %p-%p by %lux\n", p, (char*)p+n, getcallerpc(&n));
+        return p;
+}
+
+void *
+ezmalloc(ulong n)
+{
+        void *p;
+
+        p = malloc(n);
+        if(p == nil){
+                if(abortonmem)
+                        abort();
+                sysfatal("out of memory allocating %lud", n);
+        }
+        memset(p, 0, n);
+if(0)print("ezmalloc %p-%p by %lux\n", p, (char*)p+n, getcallerpc(&n));
+        return p;
+}
+
+void *
+erealloc(void *p, ulong n)
+{
+        p = realloc(p, n);
+        if(p == nil){
+                if(abortonmem)
+                        abort();
+                sysfatal("out of memory allocating %lud", n);
+        }
+if(0)print("erealloc %p-%p by %lux\n", p, (char*)p+n, getcallerpc(&p));
+        return p;
+}
+
+char *
+estrdup(char *s)
+{
+        char *t;
+        int n;
+
+        n = strlen(s) + 1;
+        t = emalloc(n);
+        memmove(t, s, n);
+if(0)print("estrdup %p-%p by %lux\n", t, (char*)t+n, getcallerpc(&s));
+        return t;
+}
+
+/*
+ * return floor(log2(v))
+ */
+int
+u64log2(u64int v)
+{
+        int i;
+
+        for(i = 0; i < 64; i++)
+                if((v >> i) <= 1)
+                        break;
+        return i;
+}
+
+int
+vtproc(void (*fn)(void*), void *arg)
+{
+        proccreate(fn, arg, 256*1024);
+        return 0;
+}
+
+int
+ientryfmt(Fmt *fmt)
+{
+        IEntry *ie;
+
+        ie = va_arg(fmt->args, IEntry*);
+        return fmtprint(fmt, "%V %22lld %3d %5d %3d",
+                ie->score, ie->ia.addr, ie->ia.type, ie->ia.size, ie->ia.blocks);
+}
+
+void
+ventifmtinstall(void)
+{
+        fmtinstall('F', vtfcallfmt);
+        fmtinstall('H', encodefmt);
+        fmtinstall('I', ientryfmt);
+        fmtinstall('V', vtscorefmt);
+}
+
+uint
+msec(void)
+{
+        return nsec()/1000000;
+}
+
+uint
+countbits(uint n)
+{
+        n = (n&0x55555555)+((n>>1)&0x55555555);
+        n = (n&0x33333333)+((n>>2)&0x33333333);
+        n = (n&0x0F0F0F0F)+((n>>4)&0x0F0F0F0F);
+        n = (n&0x00FF00FF)+((n>>8)&0x00FF00FF);
+        n = (n&0x0000FFFF)+((n>>16)&0x0000FFFF);
+        return n;
+}
diff --git a/src/cmd/venti/srv/venti.c b/src/cmd/venti/srv/venti.c
t@@ -0,0 +1,266 @@
+#ifdef PLAN9PORT
+#include 
+#include 
+#endif
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+#include "whack.h"
+
+int debug;
+int nofork;
+int mainstacksize = 256*1024;
+VtSrv *ventisrv;
+
+static void        ventiserver(void*);
+
+void
+usage(void)
+{
+        fprint(2, "usage: venti [-dw] [-a ventiaddress] [-h httpaddress] [-c config] [-C cachesize] [-I icachesize] [-B blockcachesize]\n");
+        threadexitsall("usage");
+}
+void
+threadmain(int argc, char *argv[])
+{
+        char *configfile, *haddr, *vaddr, *webroot;
+        u32int mem, icmem, bcmem, minbcmem;
+        Config config;
+
+        traceinit();
+        threadsetname("main");
+        vaddr = nil;
+        haddr = nil;
+        configfile = nil;
+        webroot = nil;
+        mem = 0;
+        icmem = 0;
+        bcmem = 0;
+        ARGBEGIN{
+        case 'a':
+                vaddr = EARGF(usage());
+                break;
+        case 'B':
+                bcmem = unittoull(EARGF(usage()));
+                break;
+        case 'c':
+                configfile = EARGF(usage());
+                break;
+        case 'C':
+                mem = unittoull(EARGF(usage()));
+                break;
+        case 'D':
+                settrace(EARGF(usage()));
+                break;
+        case 'd':
+                debug = 1;
+                nofork = 1;
+                break;
+        case 'h':
+                haddr = EARGF(usage());
+                break;
+        case 'I':
+                icmem = unittoull(EARGF(usage()));
+                break;
+        case 'L':
+                ventilogging = 1;
+                break;
+        case 's':
+                nofork = 1;
+                break;
+        case 'W':
+                webroot = EARGF(usage());
+                break;
+        default:
+                usage();
+        }ARGEND
+
+        if(argc)
+                usage();
+
+        if(!nofork)
+                rfork(RFNOTEG);
+
+#ifdef PLAN9PORT
+        {
+                /* sigh - needed to avoid signals when writing to hungup networks */
+                struct sigaction sa;
+                memset(&sa, 0, sizeof sa);
+                sa.sa_handler = SIG_IGN;
+                sigaction(SIGPIPE, &sa, nil);
+        }
+#endif
+
+        trace(TraceQuiet, "venti started");
+        fprint(2, "venti: ");
+
+        ventifmtinstall();
+        if(configfile == nil)
+                configfile = "venti.conf";
+
+        if(initarenasum() < 0)
+                fprint(2, "warning: can't initialize arena summing process: %r");
+
+        fprint(2, "conf...");
+        if(initventi(configfile, &config) < 0)
+                sysfatal("can't init server: %r");
+
+        if(mem == 0)
+                mem = config.mem;
+        if(bcmem == 0)
+                bcmem = config.bcmem;
+        if(icmem == 0)
+                icmem = config.icmem;
+        if(haddr == nil)
+                haddr = config.haddr;
+        if(vaddr == nil)
+                vaddr = config.vaddr;
+        if(vaddr == nil)
+                vaddr = "tcp!*!venti";
+        if(webroot == nil)
+                webroot = config.webroot;
+        if(queuewrites == 0)
+                queuewrites = config.queuewrites;
+
+        if(haddr){
+                fprint(2, "httpd %s...", haddr);
+                if(httpdinit(haddr, webroot) < 0)
+                        fprint(2, "warning: can't start http server: %r");
+        }
+
+        fprint(2, "init...");
+
+        if(mem == 0xffffffffUL)
+                mem = 1 * 1024 * 1024;
+        if(0) fprint(2, "initialize %d bytes of lump cache for %d lumps\n",
+                mem, mem / (8 * 1024));
+        initlumpcache(mem, mem / (8 * 1024));
+
+        icmem = u64log2(icmem / (sizeof(IEntry)+sizeof(IEntry*)) / ICacheDepth);
+        if(icmem < 4)
+                icmem = 4;
+        if(0) fprint(2, "initialize %d bytes of index cache for %d index entries\n",
+                (sizeof(IEntry)+sizeof(IEntry*)) * (1 << icmem) * ICacheDepth,
+                (1 << icmem) * ICacheDepth);
+        initicache(icmem, ICacheDepth);
+        initicachewrite();
+
+        /*
+         * need a block for every arena and every process
+         */
+        minbcmem = maxblocksize * 
+                (mainindex->narenas + mainindex->nsects*4 + 16);
+        if(bcmem < minbcmem)
+                bcmem = minbcmem;
+
+        if(0) fprint(2, "initialize %d bytes of disk block cache\n", bcmem);
+        initdcache(bcmem);
+
+        if(mainindex->bloom)
+                startbloomproc(mainindex->bloom);
+
+        fprint(2, "sync...");
+        if(syncindex(mainindex, 1, 0, 0) < 0)
+                sysfatal("can't sync server: %r");
+
+        if(queuewrites){
+                fprint(2, "queue...");
+                if(initlumpqueues(mainindex->nsects) < 0){
+                        fprint(2, "can't initialize lump queues,"
+                                " disabling write queueing: %r");
+                        queuewrites = 0;
+                }
+        }
+
+        fprint(2, "announce %s...", vaddr);
+        ventisrv = vtlisten(vaddr);
+        if(ventisrv == nil)
+                sysfatal("can't announce %s: %r", vaddr);
+
+        fprint(2, "serving.\n");
+        if(nofork)
+                ventiserver(nil);
+        else
+                vtproc(ventiserver, nil);
+}
+
+static void
+vtrerror(VtReq *r, char *error)
+{
+        r->rx.msgtype = VtRerror;
+        r->rx.error = estrdup(error);
+}
+
+static void
+ventiserver(void *v)
+{
+        Packet *p;
+        VtReq *r;
+        char err[ERRMAX];
+        uint ms;
+        int cached, ok;
+
+        USED(v);
+        threadsetname("ventiserver");
+        trace(TraceWork, "start");
+        while((r = vtgetreq(ventisrv)) != nil){
+                trace(TraceWork, "finish");
+                trace(TraceWork, "start request %F", &r->tx);
+                trace(TraceRpc, "<- %F", &r->tx);
+                r->rx.msgtype = r->tx.msgtype+1;
+                addstat(StatRpcTotal, 1);
+        //        print("req (arenas[0]=%p sects[0]=%p) %F\n",
+        //                mainindex->arenas[0], mainindex->sects[0], &r->tx);
+                switch(r->tx.msgtype){
+                default:
+                        vtrerror(r, "unknown request");
+                        break;
+                case VtTread:
+                        ms = msec();
+                        r->rx.data = readlump(r->tx.score, r->tx.blocktype, r->tx.count, &cached);
+                        ms = msec() - ms;
+                        addstat2(StatRpcRead, 1, StatRpcReadTime, ms);
+                        if(r->rx.data == nil){
+                                addstat(StatRpcReadFail, 1);
+                                rerrstr(err, sizeof err);
+                                vtrerror(r, err);
+                        }else{
+                                addstat(StatRpcReadBytes, packetsize(r->rx.data));
+                                addstat(StatRpcReadOk, 1);
+                                if(cached)
+                                        addstat2(StatRpcReadCached, 1, StatRpcReadCachedTime, ms);
+                                else
+                                        addstat2(StatRpcReadUncached, 1, StatRpcReadUncachedTime, ms);
+                        }
+                        break;
+                case VtTwrite:
+                        p = r->tx.data;
+                        r->tx.data = nil;
+                        addstat(StatRpcWriteBytes, packetsize(p));
+                        ms = msec();
+                        ok = writelump(p, r->rx.score, r->tx.blocktype, 0, ms);
+                        ms = msec() - ms;
+                        addstat2(StatRpcWrite, 1, StatRpcWriteTime, ms);
+
+                        if(ok < 0){
+                                addstat(StatRpcWriteFail, 1);
+                                rerrstr(err, sizeof err);
+                                vtrerror(r, err);
+                        }
+                        break;
+                case VtTsync:
+                        flushqueue();
+                        flushdcache();
+                        break;
+                }
+                trace(TraceRpc, "-> %F", &r->rx);
+                vtrespond(r);
+                trace(TraceWork, "start");
+        }
+        flushdcache();
+        flushicache();
+        threadexitsall(0);
+}
+
+
diff --git a/src/cmd/venti/srv/verifyarena.c b/src/cmd/venti/srv/verifyarena.c
t@@ -0,0 +1,127 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+static int        verbose;
+
+void
+usage(void)
+{
+        fprint(2, "usage: verifyarena [-v]\n");
+        threadexitsall(0);
+}
+
+static void
+readblock(uchar *buf, int n)
+{
+        int nr, m;
+
+        for(nr = 0; nr < n; nr += m){
+                m = n - nr;
+                m = read(0, &buf[nr], m);
+                if(m <= 0)
+                        sysfatal("can't read arena from standard input: %r");
+        }
+}
+
+static void
+verifyarena(void)
+{
+        Arena arena;
+        ArenaHead head;
+        ZBlock *b;
+        DigestState s;
+        u64int n, e;
+        u32int bs;
+        u8int score[VtScoreSize];
+
+        fprint(2, "verify arena from standard input\n");
+
+        memset(&arena, 0, sizeof arena);
+        memset(&s, 0, sizeof s);
+
+        /*
+         * read the little bit, which will included the header
+         */
+        bs = MaxIoSize;
+        b = alloczblock(bs, 0, 0);
+        readblock(b->data, HeadSize);
+        sha1(b->data, HeadSize, nil, &s);
+        if(unpackarenahead(&head, b->data) < 0)
+                sysfatal("corrupted arena header: %r");
+        if(head.version != ArenaVersion4 && head.version != ArenaVersion5)
+                fprint(2, "warning: unknown arena version %d\n", head.version);
+
+        /*
+         * now we know how much to read
+         * read everything but the last block, which is special
+         */
+        e = head.size - head.blocksize;
+        for(n = HeadSize; n < e; n += bs){
+                if(n + bs > e)
+                        bs = e - n;
+                readblock(b->data, bs);
+                sha1(b->data, bs, nil, &s);
+        }
+
+        /*
+         * read the last block update the sum.
+         * the sum is calculated assuming the slot for the sum is zero.
+         */
+        bs = head.blocksize;
+        readblock(b->data, bs);
+        sha1(b->data, bs-VtScoreSize, nil, &s);
+        sha1(zeroscore, VtScoreSize, nil, &s);
+        sha1(nil, 0, score, &s);
+
+        /*
+         * validity check on the trailer
+         */
+        arena.blocksize = head.blocksize;
+        if(unpackarena(&arena, b->data) < 0)
+                sysfatal("corrupted arena trailer: %r");
+        scorecp(arena.score, &b->data[arena.blocksize - VtScoreSize]);
+
+        if(namecmp(arena.name, head.name) != 0)
+                sysfatal("arena header and trailer names clash: %s vs. %s\n", head.name, arena.name);
+        if(arena.version != head.version)
+                sysfatal("arena header and trailer versions clash: %d vs. %d\n", head.version, arena.version);
+        arena.size = head.size - 2 * head.blocksize;
+
+        /*
+         * check for no checksum or the same
+         */
+        if(scorecmp(score, arena.score) != 0){
+                if(scorecmp(zeroscore, arena.score) != 0)
+                        fprint(2, "warning: mismatched checksums for arena=%s, found=%V calculated=%V",
+                                arena.name, arena.score, score);
+                scorecp(arena.score, score);
+        }else
+                fprint(2, "matched score\n");
+
+        printarena(2, &arena);
+}
+
+void
+threadmain(int argc, char *argv[])
+{
+        ventifmtinstall();
+        statsinit();
+
+        ARGBEGIN{
+        case 'v':
+                verbose++;
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        readonly = 1;
+
+        if(argc != 0)
+                usage();
+
+        verifyarena();
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/srv/whack.c b/src/cmd/venti/srv/whack.c
t@@ -0,0 +1,331 @@
+#include "stdinc.h"
+#include "whack.h"
+
+typedef struct Huff        Huff;
+int compressblocks = 1;
+
+enum
+{
+        MaxFastLen        = 9,
+        BigLenCode        = 0x1f4,        /* minimum code for large lenth encoding */
+        BigLenBits        = 9,
+        BigLenBase        = 4,                /* starting items to encode for big lens */
+
+        MinOffBits        = 6,
+        MaxOffBits        = MinOffBits + 8,
+
+        MaxLen                = 2051                /* max. length encodable in 24 bits */
+};
+
+enum
+{
+        StatBytes,
+        StatOutBytes,
+        StatLits,
+        StatMatches,
+        StatLitBits,
+        StatOffBits,
+        StatLenBits,
+
+        MaxStat
+};
+
+struct Huff
+{
+        short        bits;                                /* length of the code */
+        ulong        encode;                                /* the code */
+};
+
+static        Huff        lentab[MaxFastLen] =
+{
+        {2,        0x2},                /* 10 */
+        {3,        0x6},                /* 110 */
+        {5,        0x1c},                /* 11100 */
+        {5,        0x1d},                /* 11101 */
+        {6,        0x3c},                /* 111100 */
+        {7,        0x7a},                /* 1111010 */
+        {7,        0x7b},                /* 1111011 */
+        {8,        0xf8},                /* 11111000 */
+        {8,        0xf9},                /* 11111001 */
+};
+
+static int        thwmaxcheck;
+
+void
+whackinit(Whack *tw, int level)
+{
+        thwmaxcheck = (1 << level);
+        thwmaxcheck -= thwmaxcheck >> 2;
+        if(thwmaxcheck < 2)
+                thwmaxcheck = 2;
+        else if(thwmaxcheck > 1024)
+                thwmaxcheck = 1024;
+        memset(tw, 0, sizeof *tw);
+        tw->begin = 2 * WhackMaxOff;
+}
+
+/*
+ * find a string in the dictionary
+ */
+static int
+whackmatch(Whack *b, uchar **ss, uchar *esrc, ulong h, ulong now)
+{
+        ushort then, off, last;
+        int bestoff, bestlen, check;
+        uchar *s, *t;
+
+        s = *ss;
+        if(esrc < s + MinMatch)
+                return -1;
+        if(s + MaxLen < esrc)
+                esrc = s + MaxLen;
+
+        bestoff = 0;
+        bestlen = 0;
+        check = thwmaxcheck;
+        last = 0;
+        for(then = b->hash[h]; check-- > 0; then = b->next[then & (WhackMaxOff - 1)]){
+                off = now - then;
+                if(off <= last || off > WhackMaxOff)
+                        break;
+
+                /*
+                 * don't need to check for the end because
+                 * 1) s too close check above
+                 */
+                t = s - off;
+                if(s[0] == t[0] && s[1] == t[1] && s[2] == t[2]){
+                        if(!bestlen || esrc - s > bestlen && s[bestlen] == t[bestlen]){
+                                t += 3;
+                                for(s += 3; s < esrc; s++){
+                                        if(*s != *t)
+                                                break;
+                                        t++;
+                                }
+                                if(s - *ss > bestlen){
+                                        bestlen = s - *ss;
+                                        bestoff = off;
+                                        if(bestlen > thwmaxcheck)
+                                                break;
+                                }
+                        }
+                }
+                s = *ss;
+                last = off;
+        }
+        *ss += bestlen;
+        return bestoff;
+}
+
+/*
+ * knuth vol. 3 multiplicative hashing
+ * each byte x chosen according to rules
+ * 1/4 < x < 3/10, 1/3 x < < 3/7, 4/7 < x < 2/3, 7/10 < x < 3/4
+ * with reasonable spread between the bytes & their complements
+ *
+ * the 3 byte value appears to be as almost good as the 4 byte value,
+ * and might be faster on some machines
+ */
+/*
+#define hashit(c)        ((((ulong)(c) * 0x6b43a9) >> (24 - HashLog)) & HashMask)
+*/
+#define hashit(c)        (((((ulong)(c) & 0xffffff) * 0x6b43a9b5) >> (32 - HashLog)) & HashMask)
+
+/*
+ * lz77 compression with single lookup in a hash table for each block
+ */
+int
+whack(Whack *w, uchar *dst, uchar *src, int n, ulong stats[WhackStats])
+{
+        uchar *s, *ss, *sss, *esrc, *half, *wdst, *wdmax;
+        ulong cont, code, wbits;
+        ushort now;
+        int toff, lithist, h, len, bits, use, wnbits, lits, matches, offbits, lenbits;
+
+        if(!compressblocks || n < MinMatch)
+                return -1;
+
+        wdst = dst;
+        wdmax = dst + n;
+
+        now = w->begin;
+        s = src;
+        w->data = s;
+
+        cont = (s[0] << 16) | (s[1] << 8) | s[2];
+
+        esrc = s + n;
+        half = s + (n >> 1);
+        wnbits = 0;
+        wbits = 0;
+        lits = 0;
+        matches = 0;
+        offbits = 0;
+        lenbits = 0;
+        lithist = ~0;
+        while(s < esrc){
+                h = hashit(cont);
+
+                sss = s;
+                toff = whackmatch(w, &sss, esrc, h, now);
+                ss = sss;
+
+                len = ss - s;
+                for(; wnbits >= 8; wnbits -= 8){
+                        if(wdst >= wdmax){
+                                w->begin = now;
+                                return -1;
+                        }
+                        *wdst++ = wbits >> (wnbits - 8);
+                }
+                if(len < MinMatch){
+                        toff = *s;
+                        lithist = (lithist << 1) | toff < 32 | toff > 127;
+                        if(lithist & 0x1e){
+                                wbits = (wbits << 9) | toff;
+                                wnbits += 9;
+                        }else if(lithist & 1){
+                                toff = (toff + 64) & 0xff;
+                                if(toff < 96){
+                                        wbits = (wbits << 10) | toff;
+                                        wnbits += 10;
+                                }else{
+                                        wbits = (wbits << 11) | toff;
+                                        wnbits += 11;
+                                }
+                        }else{
+                                wbits = (wbits << 8) | toff;
+                                wnbits += 8;
+                        }
+                        lits++;
+
+                        /*
+                         * speed hack
+                         * check for compression progress, bail if none achieved
+                         */
+                        if(s > half){
+                                if(4 * (s - src) < 5 * lits){
+                                        w->begin = now;
+                                        return -1;
+                                }
+                                half = esrc;
+                        }
+
+                        if(s + MinMatch <= esrc){
+                                w->next[now & (WhackMaxOff - 1)] = w->hash[h];
+                                w->hash[h] = now;
+                                if(s + MinMatch < esrc)
+                                        cont = (cont << 8) | s[MinMatch];
+                        }
+                        now++;
+                        s++;
+                        continue;
+                }
+
+                matches++;
+
+                /*
+                 * length of match
+                 */
+                if(len > MaxLen){
+                        len = MaxLen;
+                        ss = s + len;
+                }
+                len -= MinMatch;
+                if(len < MaxFastLen){
+                        bits = lentab[len].bits;
+                        wbits = (wbits << bits) | lentab[len].encode;
+                        wnbits += bits;
+                        lenbits += bits;
+                }else{
+                        code = BigLenCode;
+                        bits = BigLenBits;
+                        use = BigLenBase;
+                        len -= MaxFastLen;
+                        while(len >= use){
+                                len -= use;
+                                code = (code + use) << 1;
+                                use <<= (bits & 1) ^ 1;
+                                bits++;
+                        }
+
+                        wbits = (wbits << bits) | (code + len);
+                        wnbits += bits;
+                        lenbits += bits;
+
+                        for(; wnbits >= 8; wnbits -= 8){
+                                if(wdst >= wdmax){
+                                        w->begin = now;
+                                        return -1;
+                                }
+                                *wdst++ = wbits >> (wnbits - 8);
+                        }
+                }
+
+                /*
+                 * offset in history
+                 */
+                toff--;
+                for(bits = MinOffBits; toff >= (1 << bits); bits++)
+                        ;
+                if(bits < MaxOffBits-1){
+                        wbits = (wbits << 3) | (bits - MinOffBits);
+                        if(bits != MinOffBits)
+                                bits--;
+                        wnbits += bits + 3;
+                        offbits += bits + 3;
+                }else{
+                        wbits = (wbits << 4) | 0xe | (bits - (MaxOffBits-1));
+                        bits--;
+                        wnbits += bits + 4;
+                        offbits += bits + 4;
+                }
+                wbits = (wbits << bits) | toff & ((1 << bits) - 1);
+
+                for(; s != ss; s++){
+                        if(s + MinMatch <= esrc){
+                                h = hashit(cont);
+                                w->next[now & (WhackMaxOff - 1)] = w->hash[h];
+                                w->hash[h] = now;
+                                if(s + MinMatch < esrc)
+                                        cont = (cont << 8) | s[MinMatch];
+                        }
+                        now++;
+                }
+        }
+
+        w->begin = now;
+
+        stats[StatBytes] += esrc - src;
+        stats[StatLits] += lits;
+        stats[StatMatches] += matches;
+        stats[StatLitBits] += (wdst - (dst + 2)) * 8 + wnbits - offbits - lenbits;
+        stats[StatOffBits] += offbits;
+        stats[StatLenBits] += lenbits;
+
+        if(wnbits & 7){
+                wbits <<= 8 - (wnbits & 7);
+                wnbits += 8 - (wnbits & 7);
+        }
+        for(; wnbits >= 8; wnbits -= 8){
+                if(wdst >= wdmax)
+                        return -1;
+                *wdst++ = wbits >> (wnbits - 8);
+        }
+
+        stats[StatOutBytes] += wdst - dst;
+
+        return wdst - dst;
+}
+
+int
+whackblock(uchar *dst, uchar *src, int ssize)
+{
+        Whack w;
+        ulong stats[MaxStat];
+        int r;
+
+        whackinit(&w, 6);
+        r = whack(&w, dst, src, ssize, stats);
+        return r;
+}
diff --git a/src/cmd/venti/srv/whack.h b/src/cmd/venti/srv/whack.h
t@@ -0,0 +1,40 @@
+typedef struct Whack                Whack;
+typedef struct Unwhack                Unwhack;
+
+enum
+{
+        WhackStats        = 8,
+        WhackErrLen        = 64,                /* max length of error message from thwack or unthwack */
+        WhackMaxOff        = 16*1024,        /* max allowed offset */
+
+        HashLog                = 14,
+        HashSize        = 1<= 8 */
+
+        MaxSeqMask        = 8,                /* number of bits in coding block mask */
+        MaxSeqStart        = 256                /* max offset of initial coding block */
+};
+
+struct Whack
+{
+        ushort                begin;                        /* time of first byte in hash */
+        ushort                hash[HashSize];
+        ushort                next[WhackMaxOff];
+        uchar                *data;
+};
+
+struct Unwhack
+{
+        char                err[WhackErrLen];
+};
+
+void        whackinit(Whack*, int level);
+void        unwhackinit(Unwhack*);
+int        whack(Whack*, uchar *dst, uchar *src, int nsrc, ulong stats[WhackStats]);
+int        unwhack(Unwhack*, uchar *dst, int ndst, uchar *src, int nsrc);
+
+int        whackblock(uchar *dst, uchar *src, int ssize);
diff --git a/src/cmd/venti/srv/wrarena.c b/src/cmd/venti/srv/wrarena.c
t@@ -0,0 +1,217 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+QLock godot;
+char *host;
+int readonly = 1;        /* for part.c */
+int mainstacksize = 256*1024;
+Channel *c;
+VtConn *z;
+int fast;        /* and a bit unsafe; only for benchmarking */
+int haveaoffset;
+int maxwrites = -1;
+
+typedef struct ZClump ZClump;
+struct ZClump
+{
+        ZBlock *lump;
+        Clump cl;
+        u64int aa;
+};
+
+void
+usage(void)
+{
+        fprint(2, "usage: wrarena [-h host] arenafile [offset]\n");
+        threadexitsall("usage");
+}
+
+void
+vtsendthread(void *v)
+{
+        ZClump zcl;
+
+        USED(v);
+        while(recv(c, &zcl) == 1){
+                if(zcl.lump == nil)
+                        break;
+                if(vtwrite(z, zcl.cl.info.score, zcl.cl.info.type, zcl.lump->data, zcl.cl.info.uncsize) < 0)
+                        sysfatal("failed writing clump %llud: %r", zcl.aa);
+                freezblock(zcl.lump);
+        }
+        /*
+         * All the send threads try to exit right when
+         * threadmain is calling threadexitsall.  
+         * Either libthread or the Linux NPTL pthreads library
+         * can't handle this condition (I suspect NPTL but have
+         * not confirmed this) and we get a seg fault in exit.
+         * I spent a day tracking this down with no success,
+         * so we're going to work around it instead by just
+         * sitting here and waiting for the threadexitsall to
+         * take effect.
+         */
+        qlock(&godot);
+}
+
+static void
+rdarena(Arena *arena, u64int offset)
+{
+        u64int a, aa, e;
+        u32int magic;
+        Clump cl;
+        uchar score[VtScoreSize];
+        ZBlock *lump;
+        ZClump zcl;
+
+        fprint(2, "wrarena: copying %s to venti\n", arena->name);
+        printarena(2, arena);
+
+        a = arena->base;
+        e = arena->base + arena->size;
+        if(offset != ~(u64int)0) {
+                if(offset >= e-a)
+                        sysfatal("bad offset %llud >= %llud\n",
+                                offset, e-a);
+                aa = offset;
+        } else
+                aa = 0;
+
+        if(maxwrites != 0)
+        for(; aa < e; aa += ClumpSize+cl.info.size) {
+                magic = clumpmagic(arena, aa);
+                if(magic == ClumpFreeMagic)
+                        break;
+                if(magic != arena->clumpmagic) {
+                //        fprint(2, "illegal clump magic number %#8.8ux offset %llud\n",
+                //                magic, aa);
+                        break;
+                }
+                lump = loadclump(arena, aa, 0, &cl, score, 0);
+                if(lump == nil) {
+                        fprint(2, "clump %llud failed to read: %r\n", aa);
+                        break;
+                }
+                if(!fast && cl.info.type != VtCorruptType) {
+                        scoremem(score, lump->data, cl.info.uncsize);
+                        if(scorecmp(cl.info.score, score) != 0) {
+                                fprint(2, "clump %llud has mismatched score\n", aa);
+                                break;
+                        }
+                        if(vttypevalid(cl.info.type) < 0) {
+                                fprint(2, "clump %llud has bad type %d\n", aa, cl.info.type);
+                                break;
+                        }
+                }
+                if(z && cl.info.type != VtCorruptType){
+                        zcl.cl = cl;
+                        zcl.lump = lump;
+                        zcl.aa = aa;
+                        send(c, &zcl);
+                }else
+                        freezblock(lump);
+                if(maxwrites>0 && --maxwrites == 0)
+                        break;
+        }
+        if(haveaoffset)
+                print("end offset %llud\n", aa);
+}
+
+void
+threadmain(int argc, char *argv[])
+{
+        int i;
+        char *file;
+        Arena *arena;
+        u64int offset, aoffset;
+        Part *part;
+        Dir *d;
+        uchar buf[8192];
+        ArenaHead head;
+        ZClump zerocl;
+
+        qlock(&godot);
+        aoffset = 0;
+        ARGBEGIN{
+        case 'f':
+                fast = 1;
+                ventidoublechecksha1 = 0;
+                break;
+        case 'h':
+                host = EARGF(usage());
+                break;
+        case 'o':
+                haveaoffset = 1;
+                aoffset = strtoull(EARGF(usage()), 0, 0);
+                break;
+        case 'M':
+                maxwrites = atoi(EARGF(usage()));
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        offset = ~(u64int)0;
+        switch(argc) {
+        default:
+                usage();
+        case 2:
+                offset = strtoull(argv[1], 0, 0);
+                /* fall through */
+        case 1:
+                file = argv[0];
+        }
+
+        fmtinstall('V', vtscorefmt);
+
+        statsinit();
+
+        if((d = dirstat(file)) == nil)
+                sysfatal("can't stat file %s: %r", file);
+
+        part = initpart(file, OREAD);
+        if(part == nil)
+                sysfatal("can't open file %s: %r", file);
+        if(readpart(part, aoffset, buf, sizeof buf) < 0)
+                sysfatal("can't read file %s: %r", file);
+
+        if(unpackarenahead(&head, buf) < 0)
+                sysfatal("corrupted arena header: %r");
+
+        if(aoffset+head.size > d->length)
+                sysfatal("arena is truncated: want %llud bytes have %llud\n",
+                        head.size, d->length);
+
+        partblocksize(part, head.blocksize);
+        initdcache(8 * MaxDiskBlock);
+
+        arena = initarena(part, aoffset, head.size, head.blocksize);
+        if(arena == nil)
+                sysfatal("initarena: %r");
+
+        if(host && strcmp(host, "/dev/null") != 0){
+                z = vtdial(host);
+                if(z == nil)
+                        sysfatal("could not connect to server: %r");
+                if(vtconnect(z) < 0)
+                        sysfatal("vtconnect: %r");
+        }else
+                z = nil;
+        
+        c = chancreate(sizeof(ZClump), 0);
+        for(i=0; i<12; i++)
+                vtproc(vtsendthread, nil);
+
+        rdarena(arena, offset);
+                if(vtsync(z) < 0)
+                        sysfatal("executing sync: %r");
+
+        memset(&zerocl, 0, sizeof zerocl);
+        for(i=0; i<12; i++)
+                send(c, &zerocl);
+        if(z){
+                vthangup(z);
+        }
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/srv/xml.c b/src/cmd/venti/srv/xml.c
t@@ -0,0 +1,68 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+#include "xml.h"
+
+void xmlarena(Hio *hout, Arena *s, char *tag, int indent){
+        xmlindent(hout, indent);
+        hprint(hout, "<%s", tag);
+        xmlaname(hout, s->name, "name");
+        xmlu32int(hout, s->version, "version");
+        xmlaname(hout, s->part->name, "partition");
+        xmlu32int(hout, s->blocksize, "blocksize");
+        xmlu64int(hout, s->base, "start");
+        xmlu64int(hout, s->base+2*s->blocksize, "stop");
+        xmlu32int(hout, s->ctime, "created");
+        xmlu32int(hout, s->wtime, "modified");
+        xmlsealed(hout, s->memstats.sealed, "sealed");
+        xmlscore(hout, s->score, "score");
+        xmlu32int(hout, s->memstats.clumps, "clumps");
+        xmlu32int(hout, s->memstats.cclumps, "compressedclumps");
+        xmlu64int(hout, s->memstats.uncsize, "data");
+        xmlu64int(hout, s->memstats.used - s->memstats.clumps * ClumpSize, "compresseddata");
+        xmlu64int(hout, s->memstats.used + s->memstats.clumps * ClumpInfoSize, "storage");
+        hprint(hout, "/>\n");
+}
+
+void xmlindex(Hio *hout, Index *s, char *tag, int indent){
+        int i;
+        xmlindent(hout, indent);
+        hprint(hout, "<%s", tag);
+        xmlaname(hout, s->name, "name");
+        xmlu32int(hout, s->version, "version");
+        xmlu32int(hout, s->blocksize, "blocksize");
+        xmlu32int(hout, s->tabsize, "tabsize");
+        xmlu32int(hout, s->buckets, "buckets");
+        xmlu32int(hout, s->div, "buckdiv");
+        hprint(hout, ">\n");
+        xmlindent(hout, indent + 1);
+        hprint(hout, "\n");
+        for(i = 0; i < s->nsects; i++)
+                xmlamap(hout, &s->smap[i], "sect", indent + 2);
+        xmlindent(hout, indent + 1);
+        hprint(hout, "\n");
+        xmlindent(hout, indent + 1);
+        hprint(hout, "\n");
+        for(i = 0; i < s->narenas; i++)
+                xmlamap(hout, &s->amap[i], "amap", indent + 2);
+        xmlindent(hout, indent + 1);
+        hprint(hout, "\n");
+        xmlindent(hout, indent + 1);
+        hprint(hout, "\n");
+        for(i = 0; i < s->narenas; i++)
+                xmlarena(hout, s->arenas[i], "arena", indent + 2);
+        xmlindent(hout, indent + 1);
+        hprint(hout, "\n");
+        xmlindent(hout, indent);
+        hprint(hout, "\n", tag);
+}
+
+void xmlamap(Hio *hout, AMap *s, char *tag, int indent){
+        xmlindent(hout, indent);
+        hprint(hout, "<%s", tag);
+        xmlaname(hout, s->name, "name");
+        xmlu64int(hout, s->start, "start");
+        xmlu64int(hout, s->stop, "stop");
+        hprint(hout, "/>\n");
+}
+
diff --git a/src/cmd/venti/srv/xml.h b/src/cmd/venti/srv/xml.h
t@@ -0,0 +1,11 @@
+void        xmlamap(Hio *hout, AMap *v, char *tag, int indent);
+void        xmlarena(Hio *hout, Arena *v, char *tag, int indent);
+void        xmlindex(Hio *hout, Index *v, char *tag, int indent);
+
+void        xmlaname(Hio *hout, char *v, char *tag);
+void        xmlscore(Hio *hout, u8int *v, char *tag);
+void        xmlsealed(Hio *hout, int v, char *tag);
+void        xmlu32int(Hio *hout, u32int v, char *tag);
+void        xmlu64int(Hio *hout, u64int v, char *tag);
+
+void        xmlindent(Hio *hout, int indent);
diff --git a/src/cmd/venti/srv/zblock.c b/src/cmd/venti/srv/zblock.c
t@@ -0,0 +1,93 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+void
+fmtzbinit(Fmt *f, ZBlock *b)
+{
+        f->runes = 0;
+        f->start = b->data;
+        f->to = f->start;
+        f->stop = (char*)f->start + b->len;
+        f->flush = nil;
+        f->farg = nil;
+        f->nfmt = 0;
+}
+
+#define ROUNDUP(p, n) ((void*)(((ulong)(p)+(n)-1)&~(ulong)((n)-1)))
+
+static char zmagic[] = "1234567890abcdefghijkl";
+
+ZBlock *
+alloczblock(u32int size, int zeroed, uint blocksize)
+{
+        uchar *p, *data;
+        ZBlock *b;
+        static ZBlock z;
+        int n;
+
+        if(blocksize == 0)
+                blocksize = 32;        /* try for cache line alignment */
+
+        n = size+32/*XXX*/+sizeof(ZBlock)+blocksize+8;
+        p = malloc(n);
+        if(p == nil){
+                seterr(EOk, "out of memory");
+                return nil;
+        }
+
+        data = ROUNDUP(p, blocksize);
+        b = ROUNDUP(data+size+32/*XXX*/, 8);
+        if(0) fprint(2, "alloc %p-%p data %p-%p b %p-%p\n",
+                p, p+n, data, data+size, b, b+1);
+        *b = z;
+        b->data = data;
+        b->free = p;
+        b->len = size;
+        b->_size = size;
+        if(zeroed)
+                memset(b->data, 0, size);
+        memmove(b->data+size, zmagic, 32/*XXX*/);
+        return b;
+}
+
+void
+freezblock(ZBlock *b)
+{
+        if(b){
+                if(memcmp(b->data+b->_size, zmagic, 32) != 0)
+                        abort();
+                memset(b->data+b->_size, 0, 32);
+                free(b->free);
+        }
+}
+
+ZBlock*
+packet2zblock(Packet *p, u32int size)
+{
+        ZBlock *b;
+
+        if(p == nil)
+                return nil;
+        b = alloczblock(size, 0, 0);
+        if(b == nil)
+                return nil;
+        if(packetcopy(p, b->data, 0, size) < 0){
+                freezblock(b);
+                return nil;
+        }
+        return b;
+}
+
+Packet*
+zblock2packet(ZBlock *zb, u32int size)
+{
+        Packet *p;
+
+        if(zb == nil)
+                return nil;
+        p = packetalloc();
+        packetappend(p, zb->data, size);
+        return p;
+}
+
diff --git a/src/cmd/venti/srv/zeropart.c b/src/cmd/venti/srv/zeropart.c
t@@ -0,0 +1,31 @@
+#include "stdinc.h"
+#include "dat.h"
+#include "fns.h"
+
+void
+zeropart(Part *part, int blocksize)
+{
+        ZBlock *b;
+        u64int addr;
+        int w;
+
+        fprint(2, "clearing the partition\n");
+//fprint(2, "NOT!\n");
+//return;
+//b=alloczblock(MaxIoSize, 1, blocksize);
+//freezblock(b);
+        b = alloczblock(MaxIoSize, 1, blocksize);
+
+        w = 0;
+        for(addr = PartBlank; addr + MaxIoSize <= part->size; addr += MaxIoSize){
+                if(writepart(part, addr, b->data, MaxIoSize) < 0)
+                        sysfatal("can't initialize %s, writing block %d failed: %r", part->name, w);
+                w++;
+        }
+
+        for(; addr + blocksize <= part->size; addr += blocksize)
+                if(writepart(part, addr, b->data, blocksize) < 0)
+                        sysfatal("can't initialize %s: %r", part->name);
+
+        freezblock(b);
+}
diff --git a/src/cmd/venti/sync.c b/src/cmd/venti/sync.c
t@@ -0,0 +1,54 @@
+#include 
+#include 
+#include 
+#include 
+
+char *host;
+int donothing;
+
+void
+usage(void)
+{
+        fprint(2, "usage: sync [-h host]\n");
+        threadexitsall("usage");
+}
+
+void
+threadmain(int argc, char *argv[])
+{
+        VtConn *z;
+
+        fmtinstall('V', vtscorefmt);
+        fmtinstall('F', vtfcallfmt);
+        
+        ARGBEGIN{
+        case 'h':
+                host = EARGF(usage());
+                if(host == nil)
+                        usage();
+                break;
+        case 'x':
+                donothing = 1;
+                break;
+        default:
+                usage();
+                break;
+        }ARGEND
+
+        if(argc != 0)
+                usage();
+
+        z = vtdial(host);
+        if(z == nil)
+                sysfatal("could not connect to server: %r");
+
+        if(vtconnect(z) < 0)
+                sysfatal("vtconnect: %r");
+
+        if(!donothing)
+        if(vtsync(z) < 0)
+                sysfatal("vtsync: %r");
+
+        vthangup(z);
+        threadexitsall(0);
+}
diff --git a/src/cmd/venti/write.c b/src/cmd/venti/write.c
t@@ -0,0 +1,62 @@
+#include 
+#include 
+#include 
+#include 
+#include 
+
+void
+usage(void)
+{
+        fprint(2, "usage: write [-z] [-h host] [-t type]  VtMaxLumpSize)
+                sysfatal("input too big: max block size is %d", VtMaxLumpSize);
+        z = vtdial(host);
+        if(z == nil)
+                sysfatal("could not connect to server: %r");
+        if(vtconnect(z) < 0)
+                sysfatal("vtconnect: %r");
+        if(dotrunc)
+                n = vtzerotruncate(type, p, n);
+        if(vtwrite(z, score, type, p, n) < 0)
+                sysfatal("vtwrite: %r");
+        vthangup(z);
+        print("%V\n", score);
+        threadexitsall(0);
+}