maintenance/fixSlaveDesync.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @ingroup Maintenance
  19  */
  20
  21 require_once( "Maintenance.php" );
  22
  23 class FixSlaveDesync extends Maintenance {
  24         public function __construct() {
  25                 parent::__construct();
  26                 $this->mDescription = "";
  27
  28         }
  29
  30         public function execute() {
  31                 global $wgUseRootUser, $wgDBservers;
  32                 $wgUseRootUser = true;
  33
  34                 $slaveIndexes = array();
  35                 for ( $i = 1; $i < count( $wgDBservers ); $i++ ) {
  36                         if ( wfGetLB()->isNonZeroLoad( $i ) ) {
  37                                 $slaveIndexes[] = $i;
  38                         }
  39                 }
  40
  41                 if ( $this->hasArg() ) {
  42                         $this->desyncFixPage( $this->getArg() );
  43                 } else {
  44                         $dbw = wfGetDB( DB_MASTER );
  45                         $maxPage = $dbw->selectField( 'page', 'MAX(page_id)', false, __METHOD__ );
  46                         $corrupt = $this->findPageLatestCorruption();
  47                         foreach ( $corrupt as $id => $dummy ) {
  48                                 $this->desyncFixPage( $id );
  49                         }
  50                 }
  51         }
  52
  53         /**
  54          * Find all pages that have a corrupted page_latest
  55          * @return array
  56          */
  57         private function findPageLatestCorruption() {
  58                 $desync = array();
  59                 $n = 0;
  60                 $dbw = wfGetDB( DB_MASTER );
  61                 $masterIDs = array();
  62                 $res = $dbw->select( 'page', array( 'page_id', 'page_latest' ), array( 'page_id<6054123' ), __METHOD__ );
  63                 $this->output( "Number of pages: " . $dbw->numRows( $res ) . "\n" );
  64                 while ( $row = $dbw->fetchObject( $res ) ) {
  65                         $masterIDs[$row->page_id] = $row->page_latest;
  66                         if ( !( ++$n % 10000 ) ) {
  67                                 $this->output( "$n\r" );
  68                         }
  69                 }
  70                 $this->output( "\n" );
  71                 $dbw->freeResult( $res );
  72
  73                 global $slaveIndexes;
  74                 foreach ( $slaveIndexes as $i ) {
  75                         $db = wfGetDB( $i );
  76                         $res = $db->select( 'page', array( 'page_id', 'page_latest' ), array( 'page_id<6054123' ), __METHOD__ );
  77                         while ( $row = $db->fetchObject( $res ) ) {
  78                                 if ( isset( $masterIDs[$row->page_id] ) && $masterIDs[$row->page_id] != $row->page_latest ) {
  79                                         $desync[$row->page_id] = true;
  80                                         $this->output( $row->page_id . "\t" );
  81                                 }
  82                         }
  83                         $db->freeResult( $res );
  84                 }
  85                 $this->output( "\n" );
  86                 return $desync;
  87         }
  88
  89         /**
  90          * Fix a broken page entry
  91          * @param $pageID int The page_id to fix
  92          */
  93         private function desyncFixPage( $pageID ) {
  94                 global $slaveIndexes;
  95
  96                 # Check for a corrupted page_latest
  97                 $dbw = wfGetDB( DB_MASTER );
  98                 $dbw->begin();
  99                 $realLatest = $dbw->selectField( 'page', 'page_latest', array( 'page_id' => $pageID ),
 100                         __METHOD__, 'FOR UPDATE' );
 101                 #list( $masterFile, $masterPos ) = $dbw->getMasterPos();
 102                 $found = false;
 103                 foreach ( $slaveIndexes as $i ) {
 104                         $db = wfGetDB( $i );
 105                         /*
 106                         if ( !$db->masterPosWait( $masterFile, $masterPos, 10 ) ) {
 107                                    $this->output( "Slave is too lagged, aborting\n" );
 108                                    $dbw->commit();
 109                                    sleep(10);
 110                                    return;
 111                         }*/
 112                         $latest = $db->selectField( 'page', 'page_latest', array( 'page_id' => $pageID ), __METHOD__ );
 113                         $max = $db->selectField( 'revision', 'MAX(rev_id)', false, __METHOD__ );
 114                         if ( $latest != $realLatest && $realLatest < $max ) {
 115                                 $this->output( "page_latest corrupted in page $pageID, server $i\n" );
 116                                 $found = true;
 117                                 break;
 118                         }
 119                 }
 120                 if ( !$found ) {
 121                         $this->output( "page_id $pageID seems fine\n" );
 122                         $dbw->commit();
 123                         return;
 124                 }
 125
 126                 # Find the missing revisions
 127                 $res = $dbw->select( 'revision', array( 'rev_id' ), array( 'rev_page' => $pageID ),
 128                         __METHOD__, 'FOR UPDATE' );
 129                 $masterIDs = array();
 130                 while ( $row = $dbw->fetchObject( $res ) ) {
 131                         $masterIDs[] = $row->rev_id;
 132                 }
 133                 $dbw->freeResult( $res );
 134
 135                 $res = $db->select( 'revision', array( 'rev_id' ), array( 'rev_page' => $pageID ), __METHOD__ );
 136                 $slaveIDs = array();
 137                 while ( $row = $db->fetchObject( $res ) ) {
 138                         $slaveIDs[] = $row->rev_id;
 139                 }
 140                 $db->freeResult( $res );
 141                 if ( count( $masterIDs ) < count( $slaveIDs ) ) {
 142                         $missingIDs = array_diff( $slaveIDs, $masterIDs );
 143                         if ( count( $missingIDs ) ) {
 144                                 $this->output( "Found " . count( $missingIDs ) . " lost in master, copying from slave... " );
 145                                 $dbFrom = $db;
 146                                 $found = true;
 147                                 $toMaster = true;
 148                         } else {
 149                                 $found = false;
 150                         }
 151                 } else {
 152                         $missingIDs = array_diff( $masterIDs, $slaveIDs );
 153                         if ( count( $missingIDs ) ) {
 154                                 $this->output( "Found " . count( $missingIDs ) . " missing revision(s), copying from master... " );
 155                                 $dbFrom = $dbw;
 156                                 $found = true;
 157                                 $toMaster = false;
 158                         } else {
 159                                 $found = false;
 160                         }
 161                 }
 162
 163                 if ( $found ) {
 164                         foreach ( $missingIDs as $rid ) {
 165                                 $this->output( "$rid " );
 166                                 # Revision
 167                                 $row = $dbFrom->selectRow( 'revision', '*', array( 'rev_id' => $rid ), __METHOD__ );
 168                                 if ( $toMaster ) {
 169                                         $id = $dbw->selectField( 'revision', 'rev_id', array( 'rev_id' => $rid ),
 170                                                 __METHOD__, 'FOR UPDATE' );
 171                                         if ( $id ) {
 172                                                 $this->output( "Revision already exists\n" );
 173                                                 $found = false;
 174                                                 break;
 175                                         } else {
 176                                                 $dbw->insert( 'revision', get_object_vars( $row ), __METHOD__, 'IGNORE' );
 177                                         }
 178                                 } else {
 179                                         foreach ( $slaveIndexes as $i ) {
 180                                                 $db = wfGetDB( $i );
 181                                                 $db->insert( 'revision', get_object_vars( $row ), __METHOD__, 'IGNORE' );
 182                                         }
 183                                 }
 184
 185                                 # Text
 186                                 $row = $dbFrom->selectRow( 'text', '*', array( 'old_id' => $row->rev_text_id ), __METHOD__ );
 187                                 if ( $toMaster ) {
 188                                         $dbw->insert( 'text', get_object_vars( $row ), __METHOD__, 'IGNORE' );
 189                                 } else {
 190                                         foreach ( $slaveIndexes as $i ) {
 191                                                 $db = wfGetDB( $i );
 192                                                 $db->insert( 'text', get_object_vars( $row ), __METHOD__, 'IGNORE' );
 193                                         }
 194                                 }
 195                         }
 196                         $this->output( "done\n" );
 197                 }
 198
 199                 if ( $found ) {
 200                         $this->output( "Fixing page_latest... " );
 201                         if ( $toMaster ) {
 202                                 #$dbw->update( 'page', array( 'page_latest' => $realLatest ), array( 'page_id' => $pageID ), __METHOD__ );
 203                         } else {
 204                                 foreach ( $slaveIndexes as $i ) {
 205                                         $db = wfGetDB( $i );
 206                                         $db->update( 'page', array( 'page_latest' => $realLatest ), array( 'page_id' => $pageID ), __METHOD__ );
 207                                 }
 208                         }
 209                         $this->output( "done\n" );
 210                 }
 211                 $dbw->commit();
 212         }
 213 }
 214
 215 $maintClass = "FixSlaveDesync";
 216 require_once( DO_MAINTENANCE );