maintenance/rebuildlinks.inc

   1 <?php
   2
   3 die( "rebuildLinks.inc needs to be updated for the new schema\n" );
   4
   5 # Functions for rebuilding the link tracking tables; must
   6 # be included within a script that also includes the Setup.
   7 # See rebuildlinks.php, for example.
   8 #
   9
  10 # Buffer this many rows before inserting them all in one sweep. More
  11 # than about 1000 will probably not increase speed significantly on
  12 # most setups.
  13 /* private */ $rowbuf_size = 1000; // 1000 rows ~40 kB
  14
  15 function rebuildLinkTables()
  16 {
  17         error_reporting (E_ALL);
  18         global $wgLang, $wgLinkCache, $rowbuf_size;
  19
  20         print "This script may take several hours to complete. If you abort during that time,\n";
  21         print "your wiki will be in an inconsistent state. If you are going to abort, this is\n";
  22         print "the time to do it.\n\n";
  23         print "Press control-c to abort (will proceed automatically in 15 seconds)\n";
  24         sleep(15);
  25
  26         $count = 0;
  27         print "Rebuilding link tables.\n";
  28
  29         print "Setting AUTOCOMMIT=1\n";
  30         wfQuery("SET SESSION AUTOCOMMIT=1", DB_WRITE);
  31
  32         print "Extracting often used data from cur (may take a few minutes)\n";
  33         $sql = "CREATE TEMPORARY TABLE cur_fast SELECT cur_namespace, cur_title, cur_id FROM cur";
  34         wfQuery( $sql, DB_WRITE );
  35         $sql = "ALTER TABLE cur_fast ADD INDEX(cur_namespace, cur_title)";
  36         wfQuery( $sql, DB_WRITE );
  37
  38         print "Locking tables\n";
  39         $sql = "LOCK TABLES cur READ, cur_fast READ, interwiki READ, user_newtalk READ, " .
  40                 "links WRITE, brokenlinks WRITE, imagelinks WRITE";
  41         wfQuery( $sql, DB_WRITE );
  42
  43
  44         print "Deleting old data in links table.\n";
  45         $sql = "DELETE FROM links";
  46         wfQuery( $sql, DB_WRITE );
  47
  48         print "Deleting old data in brokenlinks table.\n";
  49         $sql = "DELETE FROM brokenlinks";
  50         wfQuery( $sql, DB_WRITE );
  51
  52         print "Deleting old data in imagelinks table.\n";
  53         $sql = "DELETE FROM imagelinks";
  54         wfQuery( $sql, DB_WRITE );
  55
  56         print "Finding number of articles to process... ";
  57         $sql = "SELECT COUNT(*) as count FROM cur";
  58         $res = wfQuery( $sql, DB_READ );
  59         $obj = wfFetchObject( $res );
  60         $total = $obj->count;
  61         print "$total\n";
  62
  63         print "Finding highest article id\n";
  64         $sql = "SELECT MIN(cur_id) AS min, MAX(cur_id) AS max FROM cur";
  65         $res = wfQuery( $sql, DB_READ );
  66         $obj = wfFetchObject( $res );
  67
  68         $cur_pulser = new SelectPulser("SELECT cur_id,cur_namespace,cur_title,cur_text " .
  69                 "FROM cur WHERE cur_id ",
  70                 $obj->min, $obj->max, 100);
  71
  72         $brokenlinks_inserter = new InsertBuffer(
  73                 "INSERT IGNORE INTO brokenlinks (bl_from,bl_to) VALUES " , $rowbuf_size);
  74
  75         $links_inserter = new InsertBuffer(
  76                 "INSERT IGNORE INTO links (l_from,l_to) VALUES ", $rowbuf_size);
  77
  78         $imagelinks_inserter = new InsertBuffer("INSERT IGNORE INTO imagelinks ".
  79                 "(il_from,il_to) VALUES ", $rowbuf_size);
  80
  81         print "Starting processing\n";
  82
  83         $ins = $wgLang->getNsText( Namespace::getImage() );
  84         $inslen = strlen($ins)+1;
  85
  86         $tc = Title::legalChars();
  87
  88         $titleCache = new MRUCache( 10000 );
  89         $titlecount = 0;
  90         $start_time = time();
  91
  92         while ( $row = $cur_pulser->next() ) {
  93
  94                 $from_id = intval($row->cur_id);
  95                 $ns = $wgLang->getNsText( $row->cur_namespace );
  96                 $from_full_title = $row->cur_title;
  97                 if ( "" != $ns ) {
  98                         $from_full_title = "$ns:{$from_full_title}";
  99                 }
 100                 $from_full_title_with_slashes = addslashes( $from_full_title );
 101                 $text = $row->cur_text;
 102
 103                 $numlinks = preg_match_all( "/\\[\\[([{$tc}]+)(]|\\|)/", $text,
 104                   $m, PREG_PATTERN_ORDER );
 105
 106                 $seen_dbtitles = array(); // seen links (normalized and with ns, see below)
 107                 $titles_ready_for_insertion = array();
 108                 $titles_needing_curdata = array();
 109                 $titles_needing_curdata_pos = array();
 110                 $links_corresponding_to_titles = array();
 111
 112                 for ( $i = 0 ; $i < $numlinks; ++$i ) {
 113                         $link = $m[1][$i];
 114                         if( preg_match( '/^(http|https|ftp|mailto|news):/', $m[1][$i] ) ) {
 115                                 # an URL link; not for us!
 116                                 continue;
 117                         }
 118
 119                         # FIXME: Handle subpage links
 120                         $nt = $titleCache->get( $link );
 121                         if( $nt != false ){
 122                                 // Only process each unique link once per page
 123                                 $nt_key = $nt->getDBkey() . $nt->getNamespace();
 124                                 if( isset( $seen_dbtitles[$nt_key] ) )
 125                                         continue;
 126                                 $seen_dbtitles[$nt_key] = 1;
 127
 128                                 $titles_ready_for_insertion[] = $nt;
 129                         } else {
 130                                 $nt = Title::newFromText( $link );
 131                                 if (! $nt) {
 132                                         // Invalid link, probably something like "[[  ]]"
 133                                         continue;
 134                                 }
 135
 136                                 // Only process each unique link once per page
 137                                 $nt_key = $nt->getDBkey() . $nt->getNamespace();
 138                                 if( isset( $seen_dbtitles[$nt_key] ) )
 139                                         continue;
 140                                 $seen_dbtitles[$nt_key] = 1;
 141
 142                                 if( $nt->getInterwiki() != "" ) {
 143                                         # Interwiki links are not stored in the link tables
 144                                         continue;
 145                                 }
 146                                 if( $nt->getNamespace() == Namespace::getSpecial() ) {
 147                                         # Special links not stored in link tables
 148                                         continue;
 149                                 }
 150                                 if( $nt->getNamespace() == Namespace::getMedia() ) {
 151                                         # treat media: links as image: links
 152                                         $nt = Title::makeTitle( Namespace::getImage(), $nt->getDBkey() );
 153                                 }
 154                                 $nt->mArticleID = 0; // assume broken link until proven otherwise
 155
 156                                 $pos = array_push($titles_needing_curdata, $nt) - 1;
 157                                 $titles_needing_curdata_pos[$nt->getDBkey() . $nt->getNamespace()] = $pos;
 158                                 $links_corresponding_to_titles[] = $link;
 159                                 unset( $link ); // useless outside this loop, but tempting
 160                         }
 161                 }
 162
 163
 164                 if ( count( $titles_needing_curdata ) > 0 ){
 165                         $parts = array();
 166                         foreach ($titles_needing_curdata as $nt ) {
 167                                 $parts[] = " (cur_namespace = " . $nt->getNamespace() . " AND " .
 168                                         "cur_title='" . wfStrencode( $nt->getDBkey() ) . "')";
 169                         }
 170                         $sql = "SELECT cur_namespace, cur_title, cur_id FROM cur_fast WHERE " .
 171                                 implode(" OR ", $parts);
 172                         $res = wfQuery( $sql, DB_WRITE );
 173                         while($row = wfFetchObject( $res ) ){
 174                                 $pos = $titles_needing_curdata_pos[$row->cur_title . $row->cur_namespace];
 175                                 $titles_needing_curdata[$pos]->mArticleID = intval($row->cur_id);
 176                         }
 177                         for( $k = 0; $k < count( $titles_needing_curdata ) ; $k++) {
 178                                 $tmplink = $links_corresponding_to_titles[$k];
 179                                 $titleCache->set( $tmplink, $titles_needing_curdata[$k] );
 180                                 $titles_ready_for_insertion[] = $titles_needing_curdata[$k];
 181                         }
 182                 }
 183
 184                 foreach ( $titles_ready_for_insertion as $nt ) {
 185                         $dest_noslashes = $nt->getPrefixedDBkey();
 186                         $dest = addslashes( $dest_noslashes );
 187                         $dest_id = $nt->getArticleID();
 188                         $from = $from_full_title_with_slashes;
 189
 190                         # print "\nLINK '$from_full_title' ($from_id) -> '$dest' ($dest_id)\n";
 191
 192                         if ( 0 == strncmp( "$ins:", $dest_noslashes, $inslen ) ) {
 193                                 $iname = addslashes( substr( $dest_noslashes, $inslen ) );
 194                                 $imagelinks_inserter->insert( "('{$from}','{$iname}')" );
 195                         } else if ( 0 == $dest_id ) {
 196                                 $brokenlinks_inserter->insert( "({$from_id},'{$dest}')" );
 197                         } else {
 198                                 $links_inserter->insert( "('{$from}',{$dest_id})" );
 199                         }
 200                         $titlecount++;
 201                 }
 202
 203                 if ( ( $count % 20 ) == 0 )
 204                         print ".";
 205
 206                 if ( ( ++$count % 1000 ) == 0 ) {
 207                         $dt = time() - $start_time;
 208                         $start_time = time();
 209                         $rps = persec(1000, $dt);
 210                         $tps = persec($titlecount, $dt);
 211                         $titlecount = 0;
 212                         print "\n$count of $total articles scanned ({$rps} articles ".
 213                                 "and {$tps} titles per second)\n";
 214                         print "Title cache hits: " . $titleCache->getPerformance() . "%\n";
 215
 216                 }
 217
 218         }
 219
 220         print "\nFlushing insertion buffers...";
 221         $imagelinks_inserter->flush();
 222         $links_inserter->flush();
 223         $brokenlinks_inserter->flush();
 224         print "ok\n";
 225
 226         print "$count articles scanned.\n";
 227
 228         $sql = "UNLOCK TABLES";
 229         wfQuery( $sql, DB_WRITE );
 230         print "Done\n";
 231 }
 232
 233 /* private */ function persec($n, $t){
 234         if($n == 0)
 235                 return "zero";
 236         if($t == 0)
 237                 return "lots of";
 238         return intval($n/$t);
 239 }
 240
 241 # InsertBuffer increases performance slightly by inserting many rows
 242 # at once. The gain is small (<5%) when running against a local, idle
 243 # database, but may be significant in other circumstances. It also
 244 # limits the number of inserted rows uppwards, which should avoid
 245 # problems with huge articles and certain mysql settings that limits
 246 # the size of queries. It's also convenient.
 247
 248 class InsertBuffer {
 249         /* private */ var $mBuf, $mSql, $mBufcount, $mMaxsize;
 250
 251         function InsertBuffer( $sql, $bufsize ){
 252                 $this->mSql = $sql;
 253                 $this->mBuf = array();
 254                 $this->mBufcount = 0;
 255                 $this->mMaxsize = $bufsize;
 256         }
 257
 258         function insert( $value ){
 259                 // print $this->mSql . " -> " . $value . "\n";
 260                 $this->mBuf[] = $value;
 261                 $this->mBufcount++;
 262                 if($this->mBufcount > $this->mMaxsize){
 263                         $this->flush();
 264                 }
 265         }
 266
 267         function flush(){
 268                 if( $this->mBufcount > 0 ){
 269                         $sql = $this->mSql . implode(",", $this->mBuf);
 270                         wfQuery( $sql, DB_WRITE );
 271                         $this->mBuf = array();
 272                         $this->mBufcount = 0;
 273                         // print "Wrote query of size " . strlen( $sql ) . "\n";
 274                 }
 275         }
 276
 277 }
 278
 279 # Select parts from a large table by using the "BETWEEN X AND Y"
 280 # operator on the id column. Avoids buffering the whole thing in
 281 # RAM. It's also convenient.
 282
 283 class SelectPulser {
 284         /* private */ var $mSql, $mSetsize, $mPos, $mMax, $mSet;
 285
 286         function SelectPulser( $sql, $min, $max, $setsize) {
 287                 $this->mSql = $sql;
 288                 $this->mSet = array();
 289                 $this->mPos = $min;
 290                 $this->mMax = $max;
 291                 $this->mSetsize = $setsize;
 292         }
 293
 294         function next(){
 295                 $result = current( $this->mSet );
 296                 next( $this->mSet );
 297                 if( false !== $result ){
 298                         return $result;
 299                 }
 300                 while( $this->mPos <= $this->mMax ){
 301                         $this->mSet = array();
 302                         $sql = $this->mSql . " BETWEEN " . $this->mPos .
 303                                 " AND " . ($this->mPos + $this->mSetsize - 1);
 304                         $this->mPos += $this->mSetsize;
 305
 306                         $res = wfQuery( $sql, DB_READ );
 307                         while ( $row = wfFetchObject( $res ) ) {
 308                                 $this->mSet[] = $row;
 309                         }
 310                         wfFreeResult( $res );
 311                         if( count( $this->mSet ) > 0 ){
 312                                 return $this->next();
 313                         }
 314                 }
 315                 return false;
 316         }
 317 }
 318
 319 # A simple MRU for general cacheing.
 320
 321 class MRUCache {
 322         /* private */ var $mMru, $mCache, $mSize, $mPurgefreq, $nexti;
 323         /* private */ var $hits, $misses;
 324
 325         function MRUCache( $size, $purgefreq = -1 ) {
 326                 // purgefreq is 1/10 of $size if not stated
 327                 $purgefreq = ($purgefreq == -1 ? intval($size/10) : $purgefreq);
 328                 $purgefreq = ($purgefreq <= 0 ? 1 : $purgefreq);
 329
 330                 $this->mSize = $size;
 331                 $this->mMru = array();
 332                 $this->mCache = array();
 333                 $this->mPurgefreq = $purgefreq;
 334                 $this->nexti = 1;
 335                 print "purgefreq = " . $this->mPurgefreq . "\n";
 336         }
 337
 338         function get( $key ){
 339                 if ( ! array_key_exists( $key, $this->mCache) ){
 340                         $this->misses++;
 341                         return false;
 342                 }
 343                 $this->hits++;
 344                 $this->mMru[$key] = $this->nexti++;
 345                 return $this->mCache[$key];
 346         }
 347
 348         function set( $key, $value ){
 349                 $this->mMru[$key] = $this->nexti++;
 350                 $this->mCache[$key] = $value;
 351
 352                 if($this->nexti % $this->mPurgefreq == 0)
 353                         $this->purge();
 354         }
 355
 356         function purge(){
 357                 $to_remove = count( $this->mMru ) - $this->mSize;
 358                 if( $to_remove <= 0 ){
 359                         return;
 360                 }
 361                 asort( $this->mMru );
 362                 $removed = array_splice( $this->mMru, 0, $to_remove );
 363                 foreach( array_keys( $removed ) as $key ){
 364                         unset( $this->mCache[$key] );
 365                 }
 366         }
 367
 368         function getPerformance(){
 369                 $tot = $this->hits + $this->misses;
 370                 if($tot > 0)
 371                         return intval(100.0 * $this->hits / $tot);
 372                 else
 373                         return 0;
 374         }
 375 }
 376
 377 ?>