src/store_dir.cc

   1
   2 /*
   3  * $Id$
   4  *
   5  * DEBUG: section 47    Store Directory Routines
   6  * AUTHOR: Duane Wessels
   7  *
   8  * SQUID Web Proxy Cache          http://www.squid-cache.org/
   9  * ----------------------------------------------------------
  10  *
  11  *  Squid is the result of efforts by numerous individuals from
  12  *  the Internet community; see the CONTRIBUTORS file for full
  13  *  details.   Many organizations have provided support for Squid's
  14  *  development; see the SPONSORS file for full details.  Squid is
  15  *  Copyrighted (C) 2001 by the Regents of the University of
  16  *  California; see the COPYRIGHT file for full details.  Squid
  17  *  incorporates software developed and/or copyrighted by other
  18  *  sources; see the CREDITS file for full details.
  19  *
  20  *  This program is free software; you can redistribute it and/or modify
  21  *  it under the terms of the GNU General Public License as published by
  22  *  the Free Software Foundation; either version 2 of the License, or
  23  *  (at your option) any later version.
  24  *
  25  *  This program is distributed in the hope that it will be useful,
  26  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  27  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  28  *  GNU General Public License for more details.
  29  *
  30  *  You should have received a copy of the GNU General Public License
  31  *  along with this program; if not, write to the Free Software
  32  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
  33  *
  34  */
  35
  36 #include "squid.h"
  37 #include "Store.h"
  38 #include "MemObject.h"
  39 #include "SquidMath.h"
  40 #include "SquidTime.h"
  41 #include "SwapDir.h"
  42 #include "swap_log_op.h"
  43
  44 #if HAVE_STATVFS
  45 #if HAVE_SYS_STATVFS_H
  46 #include <sys/statvfs.h>
  47 #endif
  48 #endif /* HAVE_STATVFS */
  49 /* statfs() needs <sys/param.h> and <sys/mount.h> on BSD systems */
  50 #if HAVE_SYS_PARAM_H
  51 #include <sys/param.h>
  52 #endif
  53 #if HAVE_SYS_MOUNT_H
  54 #include <sys/mount.h>
  55 #endif
  56 /* Windows and Linux use sys/vfs.h */
  57 #if HAVE_SYS_VFS_H
  58 #include <sys/vfs.h>
  59 #endif
  60
  61 #include "StoreHashIndex.h"
  62
  63 static STDIRSELECT storeDirSelectSwapDirRoundRobin;
  64 static STDIRSELECT storeDirSelectSwapDirLeastLoad;
  65
  66 /*
  67  * store_dirs_rebuilding is initialized to _1_ as a hack so that
  68  * storeDirWriteCleanLogs() doesn't try to do anything unless _all_
  69  * cache_dirs have been read.  For example, without this hack, Squid
  70  * will try to write clean log files if -kparse fails (becasue it
  71  * calls fatal()).
  72  */
  73 int StoreController::store_dirs_rebuilding = 1;
  74
  75 StoreController::StoreController() : swapDir (new StoreHashIndex())
  76 {}
  77
  78 StoreController::~StoreController()
  79 {}
  80
  81 /*
  82  * This function pointer is set according to 'store_dir_select_algorithm'
  83  * in squid.conf.
  84  */
  85 STDIRSELECT *storeDirSelectSwapDir = storeDirSelectSwapDirLeastLoad;
  86
  87 void
  88 StoreController::init()
  89 {
  90     swapDir->init();
  91
  92     if (0 == strcasecmp(Config.store_dir_select_algorithm, "round-robin")) {
  93         storeDirSelectSwapDir = storeDirSelectSwapDirRoundRobin;
  94         debugs(47, 1, "Using Round Robin store dir selection");
  95     } else {
  96         storeDirSelectSwapDir = storeDirSelectSwapDirLeastLoad;
  97         debugs(47, 1, "Using Least Load store dir selection");
  98     }
  99 }
 100
 101 void
 102 StoreController::createOneStore(Store &aStore)
 103 {
 104     /*
 105      * On Windows, fork() is not available.
 106      * The following is a workaround for create store directories sequentially
 107      * when running on native Windows port.
 108      */
 109 #ifndef _SQUID_MSWIN_
 110
 111     if (fork())
 112         return;
 113
 114 #endif
 115
 116     aStore.create();
 117
 118 #ifndef _SQUID_MSWIN_
 119
 120     exit(0);
 121
 122 #endif
 123 }
 124
 125 void
 126 StoreController::create()
 127 {
 128     swapDir->create();
 129
 130 #ifndef _SQUID_MSWIN_
 131
 132     pid_t pid;
 133
 134     do {
 135         int status;
 136 #ifdef _SQUID_NEXT_
 137
 138         pid = wait3(&status, WNOHANG, NULL);
 139 #else
 140
 141         pid = waitpid(-1, &status, 0);
 142 #endif
 143
 144     } while (pid > 0 || (pid < 0 && errno == EINTR));
 145
 146 #endif
 147 }
 148
 149 /**
 150  * Determine whether the given directory can handle this object
 151  * size
 152  *
 153  * Note: if the object size is -1, then the only swapdirs that
 154  * will return true here are ones that have min and max unset,
 155  * ie any-sized-object swapdirs. This is a good thing.
 156  */
 157 bool
 158 SwapDir::objectSizeIsAcceptable(int64_t objsize) const
 159 {
 160     // If the swapdir has no range limits, then it definitely can
 161     if (min_objsize <= 0 && max_objsize == -1)
 162         return true;
 163
 164     /*
 165      * If the object size is -1 and the storedir has limits we
 166      * can't store it there.
 167      */
 168     if (objsize == -1)
 169         return false;
 170
 171     // Else, make sure that the object size will fit.
 172     return min_objsize <= objsize && max_objsize > objsize;
 173 }
 174
 175
 176 /*
 177  * This new selection scheme simply does round-robin on all SwapDirs.
 178  * A SwapDir is skipped if it is over the max_size (100%) limit, or
 179  * overloaded.
 180  */
 181 static int
 182 storeDirSelectSwapDirRoundRobin(const StoreEntry * e)
 183 {
 184     static int dirn = 0;
 185     int i;
 186     int load;
 187     RefCount<SwapDir> sd;
 188
 189     ssize_t objsize = e->objectLen();
 190     if (objsize != -1)
 191         objsize += e->mem_obj->swap_hdr_sz;
 192
 193     for (i = 0; i <= Config.cacheSwap.n_configured; i++) {
 194         if (++dirn >= Config.cacheSwap.n_configured)
 195             dirn = 0;
 196
 197         sd = dynamic_cast<SwapDir *>(INDEXSD(dirn));
 198
 199         if (sd->flags.read_only)
 200             continue;
 201
 202         if (sd->cur_size > sd->max_size)
 203             continue;
 204
 205         if (!sd->objectSizeIsAcceptable(objsize))
 206             continue;
 207
 208         /* check for error or overload condition */
 209         load = sd->canStore(*e);
 210
 211         if (load < 0 || load > 1000) {
 212             continue;
 213         }
 214
 215         return dirn;
 216     }
 217
 218     return -1;
 219 }
 220
 221 /*
 222  * Spread load across all of the store directories
 223  *
 224  * Note: We should modify this later on to prefer sticking objects
 225  * in the *tightest fit* swapdir to conserve space, along with the
 226  * actual swapdir usage. But for now, this hack will do while
 227  * testing, so you should order your swapdirs in the config file
 228  * from smallest maxobjsize to unlimited (-1) maxobjsize.
 229  *
 230  * We also have to choose nleast == nconf since we need to consider
 231  * ALL swapdirs, regardless of state. Again, this is a hack while
 232  * we sort out the real usefulness of this algorithm.
 233  */
 234 static int
 235 storeDirSelectSwapDirLeastLoad(const StoreEntry * e)
 236 {
 237     ssize_t objsize;
 238     ssize_t most_free = 0, cur_free;
 239     ssize_t least_objsize = -1;
 240     int least_load = INT_MAX;
 241     int load;
 242     int dirn = -1;
 243     int i;
 244     RefCount<SwapDir> SD;
 245
 246     /* Calculate the object size */
 247     objsize = e->objectLen();
 248
 249     if (objsize != -1)
 250         objsize += e->mem_obj->swap_hdr_sz;
 251
 252     for (i = 0; i < Config.cacheSwap.n_configured; i++) {
 253         SD = dynamic_cast<SwapDir *>(INDEXSD(i));
 254         SD->flags.selected = 0;
 255         load = SD->canStore(*e);
 256
 257         if (load < 0 || load > 1000) {
 258             continue;
 259         }
 260
 261         if (!SD->objectSizeIsAcceptable(objsize))
 262             continue;
 263
 264         if (SD->flags.read_only)
 265             continue;
 266
 267         if (SD->cur_size > SD->max_size)
 268             continue;
 269
 270         if (load > least_load)
 271             continue;
 272
 273         cur_free = SD->max_size - SD->cur_size;
 274
 275         /* If the load is equal, then look in more details */
 276         if (load == least_load) {
 277             /* closest max_objsize fit */
 278
 279             if (least_objsize != -1)
 280                 if (SD->max_objsize > least_objsize || SD->max_objsize == -1)
 281                     continue;
 282
 283             /* most free */
 284             if (cur_free < most_free)
 285                 continue;
 286         }
 287
 288         least_load = load;
 289         least_objsize = SD->max_objsize;
 290         most_free = cur_free;
 291         dirn = i;
 292     }
 293
 294     if (dirn >= 0)
 295         dynamic_cast<SwapDir *>(INDEXSD(dirn))->flags.selected = 1;
 296
 297     return dirn;
 298 }
 299
 300 /*
 301  * An entry written to the swap log MUST have the following
 302  * properties.
 303  *   1.  It MUST be a public key.  It does no good to log
 304  *       a public ADD, change the key, then log a private
 305  *       DEL.  So we need to log a DEL before we change a
 306  *       key from public to private.
 307  *   2.  It MUST have a valid (> -1) swap_filen.
 308  */
 309 void
 310 storeDirSwapLog(const StoreEntry * e, int op)
 311 {
 312     assert (e);
 313     assert(!EBIT_TEST(e->flags, KEY_PRIVATE));
 314     assert(e->swap_filen >= 0);
 315     /*
 316      * icons and such; don't write them to the swap log
 317      */
 318
 319     if (EBIT_TEST(e->flags, ENTRY_SPECIAL))
 320         return;
 321
 322     assert(op > SWAP_LOG_NOP && op < SWAP_LOG_MAX);
 323
 324     debugs(20, 3, "storeDirSwapLog: " <<
 325            swap_log_op_str[op] << " " <<
 326            e->getMD5Text() << " " <<
 327            e->swap_dirn << " " <<
 328            std::hex << std::uppercase << std::setfill('0') << std::setw(8) << e->swap_filen);
 329
 330     dynamic_cast<SwapDir *>(INDEXSD(e->swap_dirn))->logEntry(*e, op);
 331 }
 332
 333 void
 334 StoreController::updateSize(int64_t size, int sign)
 335 {
 336     fatal("StoreController has no independent size\n");
 337 }
 338
 339 void
 340 SwapDir::updateSize(int64_t size, int sign)
 341 {
 342     int64_t blks = (size + fs.blksize - 1) / fs.blksize;
 343     int64_t k = ((blks * fs.blksize) >> 10) * sign;
 344     cur_size += k;
 345     store_swap_size += k;
 346
 347     if (sign > 0)
 348         n_disk_objects++;
 349     else if (sign < 0)
 350         n_disk_objects--;
 351 }
 352
 353 void
 354 StoreController::stat(StoreEntry &output) const
 355 {
 356     storeAppendPrintf(&output, "Store Directory Statistics:\n");
 357     storeAppendPrintf(&output, "Store Entries          : %lu\n",
 358                       (unsigned long int)StoreEntry::inUseCount());
 359     storeAppendPrintf(&output, "Maximum Swap Size      : %"PRIu64" KB\n",
 360                       maxSize());
 361     storeAppendPrintf(&output, "Current Store Swap Size: %8lu KB\n",
 362                       store_swap_size);
 363     storeAppendPrintf(&output, "Current Capacity       : %"PRId64"%% used, %"PRId64"%% free\n",
 364                       Math::int64Percent(store_swap_size, maxSize()),
 365                       Math::int64Percent((maxSize() - store_swap_size), maxSize()));
 366     /* FIXME Here we should output memory statistics */
 367
 368     /* now the swapDir */
 369     swapDir->stat(output);
 370 }
 371
 372 /* if needed, this could be taught to cache the result */
 373 uint64_t
 374 StoreController::maxSize() const
 375 {
 376     /* TODO: include memory cache ? */
 377     return swapDir->maxSize();
 378 }
 379
 380 uint64_t
 381 StoreController::minSize() const
 382 {
 383     /* TODO: include memory cache ? */
 384     return swapDir->minSize();
 385 }
 386
 387 void
 388 SwapDir::diskFull()
 389 {
 390     if (cur_size >= max_size)
 391         return;
 392
 393     max_size = cur_size;
 394
 395     debugs(20, 1, "WARNING: Shrinking cache_dir #" << index << " to " << cur_size << " KB");
 396 }
 397
 398 void
 399 storeDirOpenSwapLogs(void)
 400 {
 401     for (int dirn = 0; dirn < Config.cacheSwap.n_configured; ++dirn)
 402         dynamic_cast<SwapDir *>(INDEXSD(dirn))->openLog();
 403 }
 404
 405 void
 406 storeDirCloseSwapLogs(void)
 407 {
 408     for (int dirn = 0; dirn < Config.cacheSwap.n_configured; ++dirn)
 409         dynamic_cast<SwapDir *>(INDEXSD(dirn))->closeLog();
 410 }
 411
 412 /*
 413  *  storeDirWriteCleanLogs
 414  *
 415  *  Writes a "clean" swap log file from in-memory metadata.
 416  *  This is a rewrite of the original function to troll each
 417  *  StoreDir and write the logs, and flush at the end of
 418  *  the run. Thanks goes to Eric Stern, since this solution
 419  *  came out of his COSS code.
 420  */
 421 int
 422 storeDirWriteCleanLogs(int reopen)
 423 {
 424     const StoreEntry *e = NULL;
 425     int n = 0;
 426
 427     struct timeval start;
 428     double dt;
 429     RefCount<SwapDir> sd;
 430     int dirn;
 431     int notdone = 1;
 432
 433     if (StoreController::store_dirs_rebuilding) {
 434         debugs(20, 1, "Not currently OK to rewrite swap log.");
 435         debugs(20, 1, "storeDirWriteCleanLogs: Operation aborted.");
 436         return 0;
 437     }
 438
 439     debugs(20, 1, "storeDirWriteCleanLogs: Starting...");
 440     getCurrentTime();
 441     start = current_time;
 442
 443     for (dirn = 0; dirn < Config.cacheSwap.n_configured; dirn++) {
 444         sd = dynamic_cast<SwapDir *>(INDEXSD(dirn));
 445
 446         if (sd->writeCleanStart() < 0) {
 447             debugs(20, 1, "log.clean.start() failed for dir #" << sd->index);
 448             continue;
 449         }
 450     }
 451
 452     /*
 453      * This may look inefficient as CPU wise it is more efficient to do this
 454      * sequentially, but I/O wise the parallellism helps as it allows more
 455      * hdd spindles to be active.
 456      */
 457     while (notdone) {
 458         notdone = 0;
 459
 460         for (dirn = 0; dirn < Config.cacheSwap.n_configured; dirn++) {
 461             sd = dynamic_cast<SwapDir *>(INDEXSD(dirn));
 462
 463             if (NULL == sd->cleanLog)
 464                 continue;
 465
 466             e = sd->cleanLog->nextEntry();
 467
 468             if (!e)
 469                 continue;
 470
 471             notdone = 1;
 472
 473             if (!sd->canLog(*e))
 474                 continue;
 475
 476             sd->cleanLog->write(*e);
 477
 478             if ((++n & 0xFFFF) == 0) {
 479                 getCurrentTime();
 480                 debugs(20, 1, "  " << std::setw(7) << n  <<
 481                        " entries written so far.");
 482             }
 483         }
 484     }
 485
 486     /* Flush */
 487     for (dirn = 0; dirn < Config.cacheSwap.n_configured; dirn++)
 488         dynamic_cast<SwapDir *>(INDEXSD(dirn))->writeCleanDone();
 489
 490     if (reopen)
 491         storeDirOpenSwapLogs();
 492
 493     getCurrentTime();
 494
 495     dt = tvSubDsec(start, current_time);
 496
 497     debugs(20, 1, "  Finished.  Wrote " << n << " entries.");
 498     debugs(20, 1, "  Took "<< std::setw(3)<< std::setprecision(2) << dt <<
 499            " seconds ("<< std::setw(6) << ((double) n / (dt > 0.0 ? dt : 1.0)) << " entries/sec).");
 500
 501
 502     return n;
 503 }
 504
 505 StoreSearch *
 506 StoreController::search(String const url, HttpRequest *request)
 507 {
 508     /* cheat, for now you can't search the memory hot cache */
 509     return swapDir->search(url, request);
 510 }
 511
 512 StorePointer
 513 StoreHashIndex::store(int const x) const
 514 {
 515     return INDEXSD(x);
 516 }
 517
 518 void
 519 StoreController::sync(void)
 520 {
 521     /* sync mem cache? */
 522     swapDir->sync();
 523 }
 524
 525 /*
 526  * handle callbacks all avaliable fs'es
 527  */
 528 int
 529 StoreController::callback()
 530 {
 531     /* This will likely double count. Thats ok. */
 532     PROF_start(storeDirCallback);
 533
 534     /* mem cache callbacks ? */
 535     int result = swapDir->callback();
 536
 537     PROF_stop(storeDirCallback);
 538
 539     return result;
 540 }
 541
 542 int
 543 storeDirGetBlkSize(const char *path, int *blksize)
 544 {
 545 #if HAVE_STATVFS
 546
 547     struct statvfs sfs;
 548
 549     if (statvfs(path, &sfs)) {
 550         debugs(50, 1, "" << path << ": " << xstrerror());
 551         *blksize = 2048;
 552         return 1;
 553     }
 554
 555     *blksize = (int) sfs.f_frsize;
 556 #else
 557
 558     struct statfs sfs;
 559
 560     if (statfs(path, &sfs)) {
 561         debugs(50, 1, "" << path << ": " << xstrerror());
 562         *blksize = 2048;
 563         return 1;
 564     }
 565
 566     *blksize = (int) sfs.f_bsize;
 567 #endif
 568     /*
 569      * Sanity check; make sure we have a meaningful value.
 570      */
 571
 572     if (*blksize < 512)
 573         *blksize = 2048;
 574
 575     return 0;
 576 }
 577
 578 #define fsbtoblk(num, fsbs, bs) \
 579     (((fsbs) != 0 && (fsbs) < (bs)) ? \
 580             (num) / ((bs) / (fsbs)) : (num) * ((fsbs) / (bs)))
 581 int
 582 storeDirGetUFSStats(const char *path, int *totl_kb, int *free_kb, int *totl_in, int *free_in)
 583 {
 584 #if HAVE_STATVFS
 585
 586     struct statvfs sfs;
 587
 588     if (statvfs(path, &sfs)) {
 589         debugs(50, 1, "" << path << ": " << xstrerror());
 590         return 1;
 591     }
 592
 593     *totl_kb = (int) fsbtoblk(sfs.f_blocks, sfs.f_frsize, 1024);
 594     *free_kb = (int) fsbtoblk(sfs.f_bfree, sfs.f_frsize, 1024);
 595     *totl_in = (int) sfs.f_files;
 596     *free_in = (int) sfs.f_ffree;
 597 #else
 598
 599     struct statfs sfs;
 600
 601     if (statfs(path, &sfs)) {
 602         debugs(50, 1, "" << path << ": " << xstrerror());
 603         return 1;
 604     }
 605
 606     *totl_kb = (int) fsbtoblk(sfs.f_blocks, sfs.f_bsize, 1024);
 607     *free_kb = (int) fsbtoblk(sfs.f_bfree, sfs.f_bsize, 1024);
 608     *totl_in = (int) sfs.f_files;
 609     *free_in = (int) sfs.f_ffree;
 610 #endif
 611
 612     return 0;
 613 }
 614
 615 void
 616 allocate_new_swapdir(SquidConfig::_cacheSwap * swap)
 617 {
 618     if (swap->swapDirs == NULL) {
 619         swap->n_allocated = 4;
 620         swap->swapDirs = static_cast<StorePointer *>(xcalloc(swap->n_allocated, sizeof(StorePointer)));
 621     }
 622
 623     if (swap->n_allocated == swap->n_configured) {
 624         StorePointer *tmp;
 625         swap->n_allocated <<= 1;
 626         tmp = static_cast<StorePointer *>(xcalloc(swap->n_allocated, sizeof(StorePointer)));
 627         memcpy(tmp, swap->swapDirs, swap->n_configured * sizeof(SwapDir *));
 628         xfree(swap->swapDirs);
 629         swap->swapDirs = tmp;
 630     }
 631 }
 632
 633 void
 634 free_cachedir(SquidConfig::_cacheSwap * swap)
 635 {
 636     int i;
 637     /* DON'T FREE THESE FOR RECONFIGURE */
 638
 639     if (reconfiguring)
 640         return;
 641
 642     for (i = 0; i < swap->n_configured; i++) {
 643         /* TODO XXX this lets the swapdir free resources asynchronously
 644         * swap->swapDirs[i]->deactivate();
 645         * but there may be such a means already.
 646         * RBC 20041225
 647         */
 648         swap->swapDirs[i] = NULL;
 649     }
 650
 651     safe_free(swap->swapDirs);
 652     swap->swapDirs = NULL;
 653     swap->n_allocated = 0;
 654     swap->n_configured = 0;
 655 }
 656
 657 /* this should be a virtual method on StoreEntry,
 658  * i.e. e->referenced()
 659  * so that the entry can notify the creating Store
 660  */
 661 void
 662 StoreController::reference(StoreEntry &e)
 663 {
 664     /* Notify the fs that we're referencing this object again */
 665
 666     if (e.swap_dirn > -1)
 667         e.store()->reference(e);
 668
 669     /* Notify the memory cache that we're referencing this object again */
 670     if (e.mem_obj) {
 671         if (mem_policy->Referenced)
 672             mem_policy->Referenced(mem_policy, &e, &e.mem_obj->repl);
 673     }
 674 }
 675
 676 void
 677 StoreController::dereference(StoreEntry & e)
 678 {
 679     /* Notify the fs that we're not referencing this object any more */
 680
 681     if (e.swap_filen > -1)
 682         e.store()->dereference(e);
 683
 684     /* Notify the memory cache that we're not referencing this object any more */
 685     if (e.mem_obj) {
 686         if (mem_policy->Dereferenced)
 687             mem_policy->Dereferenced(mem_policy, &e, &e.mem_obj->repl);
 688     }
 689 }
 690
 691 StoreEntry *
 692 StoreController::get(const cache_key *key)
 693 {
 694     if (StoreEntry *e = swapDir->get(key)) {
 695         debugs(20, 1, HERE << "got in-transit entry: " << *e);
 696         return e;
 697     }
 698
 699     if (const int cacheDirs = Config.cacheSwap.n_configured) {
 700         // ask each cache_dir until the entry is found; use static starting
 701         // point to avoid asking the same subset of disks more often
 702         // TODO: coordinate with put() to be able to guess the right disk often
 703         for (int n = 0; n < cacheDirs; ++n) {
 704             static int idx = 0;
 705             SwapDir *sd = dynamic_cast<SwapDir*>(INDEXSD(idx));
 706             if (StoreEntry *e = sd->get(key)) {
 707                 debugs(20, 1, HERE << "cache_dir " << idx <<
 708                     " got cached entry: " << *e);
 709                 return e;
 710             }
 711             idx = (idx + 1) % cacheDirs;
 712         }
 713     }
 714
 715     debugs(20, 1, HERE << "none of " << Config.cacheSwap.n_configured <<
 716         " cache_dirs have " << storeKeyText(key));
 717     return NULL;
 718 }
 719
 720 void
 721 StoreController::get(String const key, STOREGETCLIENT aCallback, void *aCallbackData)
 722 {
 723     fatal("not implemented");
 724 }
 725
 726 StoreHashIndex::StoreHashIndex()
 727 {
 728     if (store_table)
 729         abort();
 730     assert (store_table == NULL);
 731 }
 732
 733 StoreHashIndex::~StoreHashIndex()
 734 {
 735     if (store_table) {
 736         hashFreeItems(store_table, destroyStoreEntry);
 737         hashFreeMemory(store_table);
 738         store_table = NULL;
 739     }
 740 }
 741
 742 int
 743 StoreHashIndex::callback()
 744 {
 745     int result = 0;
 746     int j;
 747     static int ndir = 0;
 748
 749     do {
 750         j = 0;
 751
 752         for (int i = 0; i < Config.cacheSwap.n_configured; i++) {
 753             if (ndir >= Config.cacheSwap.n_configured)
 754                 ndir = ndir % Config.cacheSwap.n_configured;
 755
 756             int temp_result = store(ndir)->callback();
 757
 758             ++ndir;
 759
 760             j += temp_result;
 761
 762             result += temp_result;
 763
 764             if (j > 100)
 765                 fatal ("too much io\n");
 766         }
 767     } while (j > 0);
 768
 769     ndir++;
 770
 771     return result;
 772 }
 773
 774 void
 775 StoreHashIndex::create()
 776 {
 777     for (int i = 0; i < Config.cacheSwap.n_configured; i++)
 778         store(i)->create();
 779 }
 780
 781 /* Lookup an object in the cache.
 782  * return just a reference to object, don't start swapping in yet. */
 783 StoreEntry *
 784 StoreHashIndex::get(const cache_key *key)
 785 {
 786     PROF_start(storeGet);
 787     debugs(20, 3, "storeGet: looking up " << storeKeyText(key));
 788     StoreEntry *p = static_cast<StoreEntry *>(hash_lookup(store_table, key));
 789     PROF_stop(storeGet);
 790     return p;
 791 }
 792
 793 void
 794 StoreHashIndex::get(String const key, STOREGETCLIENT aCallback, void *aCallbackData)
 795 {
 796     fatal("not implemented");
 797 }
 798
 799 void
 800 StoreHashIndex::init()
 801 {
 802     /* Calculate size of hash table (maximum currently 64k buckets).  */
 803     /* this is very bogus, its specific to the any Store maintaining an
 804      * in-core index, not global */
 805     size_t buckets = (Store::Root().maxSize() + ( Config.memMaxSize >> 10)) / Config.Store.avgObjectSize;
 806     debugs(20, 1, "Swap maxSize " << Store::Root().maxSize() <<
 807            " + " << ( Config.memMaxSize >> 10) << " KB, estimated " << buckets << " objects");
 808     buckets /= Config.Store.objectsPerBucket;
 809     debugs(20, 1, "Target number of buckets: " << buckets);
 810     /* ideally the full scan period should be configurable, for the
 811      * moment it remains at approximately 24 hours.  */
 812     store_hash_buckets = storeKeyHashBuckets(buckets);
 813     debugs(20, 1, "Using " << store_hash_buckets << " Store buckets");
 814     debugs(20, 1, "Max Mem  size: " << ( Config.memMaxSize >> 10) << " KB");
 815     debugs(20, 1, "Max Swap size: " << Store::Root().maxSize() << " KB");
 816
 817     store_table = hash_create(storeKeyHashCmp,
 818                               store_hash_buckets, storeKeyHashHash);
 819
 820     for (int i = 0; i < Config.cacheSwap.n_configured; i++) {
 821         /* this starts a search of the store dirs, loading their
 822          * index. under the new Store api this should be
 823          * driven by the StoreHashIndex, not by each store.
 824         *
 825         * That is, the HashIndex should perform a search of each dir it is
 826         * indexing to do the hash insertions. The search is then able to
 827         * decide 'from-memory', or 'from-clean-log' or 'from-dirty-log' or
 828         * 'from-no-log'.
 829         *
 830          * Step 1: make the store rebuilds use a search internally
 831         * Step 2: change the search logic to use the four modes described
 832         *         above
 833         * Step 3: have the hash index walk the searches itself.
 834          */
 835         store(i)->init();
 836     }
 837 }
 838
 839 uint64_t
 840 StoreHashIndex::maxSize() const
 841 {
 842     uint64_t result = 0;
 843
 844     for (int i = 0; i < Config.cacheSwap.n_configured; i++)
 845         result += store(i)->maxSize();
 846
 847     return result;
 848 }
 849
 850 uint64_t
 851 StoreHashIndex::minSize() const
 852 {
 853     uint64_t result = 0;
 854
 855     for (int i = 0; i < Config.cacheSwap.n_configured; i++)
 856         result += store(i)->minSize();
 857
 858     return result;
 859 }
 860
 861 void
 862 StoreHashIndex::stat(StoreEntry & output) const
 863 {
 864     int i;
 865
 866     /* Now go through each store, calling its stat routine */
 867
 868     for (i = 0; i < Config.cacheSwap.n_configured; i++) {
 869         storeAppendPrintf(&output, "\n");
 870         store(i)->stat(output);
 871     }
 872 }
 873
 874 void
 875 StoreHashIndex::reference(StoreEntry&)
 876 {}
 877
 878 void
 879 StoreHashIndex::dereference(StoreEntry&)
 880 {}
 881
 882 void
 883 StoreHashIndex::maintain()
 884 {
 885     int i;
 886     /* walk each fs */
 887
 888     for (i = 0; i < Config.cacheSwap.n_configured; i++) {
 889         /* XXX FixMe: This should be done "in parallell" on the different
 890          * cache_dirs, not one at a time.
 891          */
 892         /* call the maintain function .. */
 893         store(i)->maintain();
 894     }
 895 }
 896
 897 void
 898 StoreHashIndex::updateSize(int64_t, int)
 899 {}
 900
 901 void
 902 StoreHashIndex::sync()
 903 {
 904     for (int i = 0; i < Config.cacheSwap.n_configured; ++i)
 905         store(i)->sync();
 906 }
 907
 908 StoreSearch *
 909 StoreHashIndex::search(String const url, HttpRequest *)
 910 {
 911     if (url.size())
 912         fatal ("Cannot search by url yet\n");
 913
 914     return new StoreSearchHashIndex (this);
 915 }
 916
 917 CBDATA_CLASS_INIT(StoreSearchHashIndex);
 918
 919 StoreSearchHashIndex::StoreSearchHashIndex(RefCount<StoreHashIndex> aSwapDir) : sd(aSwapDir), _done (false), bucket (0)
 920 {}
 921
 922 /* do not link
 923 StoreSearchHashIndex::StoreSearchHashIndex(StoreSearchHashIndex const &);
 924 */
 925
 926 StoreSearchHashIndex::~StoreSearchHashIndex()
 927 {}
 928
 929 void
 930 StoreSearchHashIndex::next(void (aCallback)(void *), void *aCallbackData)
 931 {
 932     next();
 933     aCallback (aCallbackData);
 934 }
 935
 936 bool
 937 StoreSearchHashIndex::next()
 938 {
 939     if (entries.size())
 940         entries.pop_back();
 941
 942     while (!isDone() && !entries.size())
 943         copyBucket();
 944
 945     return currentItem() != NULL;
 946 }
 947
 948 bool
 949 StoreSearchHashIndex::error() const
 950 {
 951     return false;
 952 }
 953
 954 bool
 955 StoreSearchHashIndex::isDone() const
 956 {
 957     return bucket >= store_hash_buckets || _done;
 958 }
 959
 960 StoreEntry *
 961 StoreSearchHashIndex::currentItem()
 962 {
 963     if (!entries.size())
 964         return NULL;
 965
 966     return entries.back();
 967 }
 968
 969 void
 970 StoreSearchHashIndex::copyBucket()
 971 {
 972     /* probably need to lock the store entries...
 973      * we copy them all to prevent races on the links. */
 974     debugs(47, 3, "StoreSearchHashIndex::copyBucket #" << bucket);
 975     assert (!entries.size());
 976     hash_link *link_ptr = NULL;
 977     hash_link *link_next = NULL;
 978     link_next = hash_get_bucket(store_table, bucket);
 979
 980     while (NULL != (link_ptr = link_next)) {
 981         link_next = link_ptr->next;
 982         StoreEntry *e = (StoreEntry *) link_ptr;
 983
 984         entries.push_back(e);
 985     }
 986
 987     bucket++;
 988     debugs(47,3, "got entries: " << entries.size());
 989 }