maintenance/storage/testCompression.php

   1 <?php
   2 /**
   3  * Test revision text compression and decompression.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Maintenance ExternalStorage
  22  */
  23
  24 $optionsWithArgs = array( 'start', 'limit', 'type' );
  25 require( __DIR__ . '/../commandLine.inc' );
  26
  27 if ( !isset( $args[0] )  ) {
  28         echo "Usage: php testCompression.php [--type=<type>] [--start=<start-date>] [--limit=<num-revs>] <page-title>\n";
  29         exit( 1 );
  30 }
  31
  32 $title = Title::newFromText( $args[0] );
  33 if ( isset( $options['start'] ) ) {
  34         $start = wfTimestamp( TS_MW, strtotime( $options['start'] ) );
  35         echo "Starting from " . $wgLang->timeanddate( $start ) . "\n";
  36 } else {
  37         $start = '19700101000000';
  38 }
  39 if ( isset( $options['limit'] ) ) {
  40         $limit = $options['limit'];
  41         $untilHappy = false;
  42 } else {
  43         $limit = 1000;
  44         $untilHappy = true;
  45 }
  46 $type = isset( $options['type'] ) ? $options['type'] : 'ConcatenatedGzipHistoryBlob';
  47
  48
  49 $dbr = wfGetDB( DB_SLAVE );
  50 $res = $dbr->select(
  51         array( 'page', 'revision', 'text' ),
  52         '*',
  53         array(
  54                 'page_namespace' => $title->getNamespace(),
  55                 'page_title' => $title->getDBkey(),
  56                 'page_id=rev_page',
  57                 'rev_timestamp > ' . $dbr->addQuotes( $dbr->timestamp( $start ) ),
  58                 'rev_text_id=old_id'
  59         ), __FILE__, array( 'LIMIT' => $limit )
  60 );
  61
  62 $blob = new $type;
  63 $hashes = array();
  64 $keys = array();
  65 $uncompressedSize = 0;
  66 $t = -microtime( true );
  67 foreach ( $res as $row ) {
  68         $revision = new Revision( $row );
  69         $text = $revision->getSerializedData();
  70         $uncompressedSize += strlen( $text );
  71         $hashes[$row->rev_id] = md5( $text );
  72         $keys[$row->rev_id] = $blob->addItem( $text );
  73         if ( $untilHappy && !$blob->isHappy() ) {
  74                 break;
  75         }
  76 }
  77
  78 $serialized = serialize( $blob );
  79 $t += microtime( true );
  80 # print_r( $blob->mDiffMap );
  81
  82 printf( "%s\nCompression ratio for %d revisions: %5.2f, %s -> %d\n",
  83         $type,
  84         count( $hashes ),
  85         $uncompressedSize / strlen( $serialized ),
  86         $wgLang->formatSize( $uncompressedSize ),
  87         strlen( $serialized )
  88 );
  89 printf( "Compression time: %5.2f ms\n", $t * 1000 );
  90
  91 $t = -microtime( true );
  92 $blob = unserialize( $serialized );
  93 foreach ( $keys as $id => $key ) {
  94         $text = $blob->getItem( $key );
  95         if ( md5( $text ) != $hashes[$id] ) {
  96                 echo "Content hash mismatch for rev_id $id\n";
  97                 # var_dump( $text );
  98         }
  99 }
 100 $t += microtime( true );
 101 printf( "Decompression time: %5.2f ms\n", $t * 1000 );