From cb95e110f06586f23a73bf42ec595b40496ae51e Mon Sep 17 00:00:00 2001 From: Aaron Schulz Date: Sun, 10 Mar 2013 00:06:02 -0800 Subject: [PATCH] Refactored use of $wgMemc in JobQueueDB to use a field. * Also made sure it avoids SqlBagOStuff for sanity. Change-Id: If39784567392a8a2c8a0787447267d73a0aeb0f2 --- includes/job/JobQueueDB.php | 62 ++++++++++++++++--------------------- 1 file changed, 27 insertions(+), 35 deletions(-) diff --git a/includes/job/JobQueueDB.php b/includes/job/JobQueueDB.php index 4b22e942ed..379f0105a6 100644 --- a/includes/job/JobQueueDB.php +++ b/includes/job/JobQueueDB.php @@ -34,6 +34,9 @@ class JobQueueDB extends JobQueue { const MAX_JOB_RANDOM = 2147483647; // integer; 2^31 - 1, used for job_random const MAX_OFFSET = 255; // integer; maximum number of rows to skip + /** @var BagOStuff */ + protected $cache; + protected $cluster = false; // string; name of an external DB cluster /** @@ -45,8 +48,13 @@ class JobQueueDB extends JobQueue { * @param $params array */ protected function __construct( array $params ) { + global $wgMemc; + parent::__construct( $params ); + $this->cluster = isset( $params['cluster'] ) ? $params['cluster'] : false; + // Make sure that we don't use the SQL cache, which would be harmful + $this->cache = ( $wgMemc instanceof SqlBagOStuff ) ? new EmptyBagOStuff() : $wgMemc; } protected function supportedOrders() { @@ -62,11 +70,9 @@ class JobQueueDB extends JobQueue { * @return bool */ protected function doIsEmpty() { - global $wgMemc; - $key = $this->getCacheKey( 'empty' ); - $isEmpty = $wgMemc->get( $key ); + $isEmpty = $this->cache->get( $key ); if ( $isEmpty === 'true' ) { return true; } elseif ( $isEmpty === 'false' ) { @@ -77,7 +83,7 @@ class JobQueueDB extends JobQueue { $found = $dbr->selectField( // unclaimed job 'job', '1', array( 'job_cmd' => $this->type, 'job_token' => '' ), __METHOD__ ); - $wgMemc->add( $key, $found ? 'false' : 'true', self::CACHE_TTL_LONG ); + $this->cache->add( $key, $found ? 'false' : 'true', self::CACHE_TTL_LONG ); return !$found; } @@ -87,11 +93,9 @@ class JobQueueDB extends JobQueue { * @return integer */ protected function doGetSize() { - global $wgMemc; - $key = $this->getCacheKey( 'size' ); - $size = $wgMemc->get( $key ); + $size = $this->cache->get( $key ); if ( is_int( $size ) ) { return $size; } @@ -101,7 +105,7 @@ class JobQueueDB extends JobQueue { array( 'job_cmd' => $this->type, 'job_token' => '' ), __METHOD__ ); - $wgMemc->set( $key, $size, self::CACHE_TTL_SHORT ); + $this->cache->set( $key, $size, self::CACHE_TTL_SHORT ); return $size; } @@ -111,15 +115,13 @@ class JobQueueDB extends JobQueue { * @return integer */ protected function doGetAcquiredCount() { - global $wgMemc; - if ( $this->claimTTL <= 0 ) { return 0; // no acknowledgements } $key = $this->getCacheKey( 'acquiredcount' ); - $count = $wgMemc->get( $key ); + $count = $this->cache->get( $key ); if ( is_int( $count ) ) { return $count; } @@ -129,7 +131,7 @@ class JobQueueDB extends JobQueue { array( 'job_cmd' => $this->type, "job_token != {$dbr->addQuotes( '' )}" ), __METHOD__ ); - $wgMemc->set( $key, $count, self::CACHE_TTL_SHORT ); + $this->cache->set( $key, $count, self::CACHE_TTL_SHORT ); return $count; } @@ -159,12 +161,11 @@ class JobQueueDB extends JobQueue { $key = $this->getCacheKey( 'empty' ); $atomic = ( $flags & self::QoS_Atomic ); + $cache = $this->cache; $dbw->onTransactionIdle( - function() use ( $dbw, $rowSet, $rowList, $atomic, $key, $scope + function() use ( $dbw, $cache, $rowSet, $rowList, $atomic, $key, $scope ) { - global $wgMemc; - if ( $atomic ) { $dbw->begin( __METHOD__ ); // wrap all the job additions in one transaction } @@ -203,7 +204,7 @@ class JobQueueDB extends JobQueue { $dbw->commit( __METHOD__ ); } - $wgMemc->set( $key, 'false', JobQueueDB::CACHE_TTL_LONG ); + $cache->set( $key, 'false', JobQueueDB::CACHE_TTL_LONG ); } ); } @@ -215,9 +216,7 @@ class JobQueueDB extends JobQueue { * @return Job|bool */ protected function doPop() { - global $wgMemc; - - if ( $wgMemc->get( $this->getCacheKey( 'empty' ) ) === 'true' ) { + if ( $this->cache->get( $this->getCacheKey( 'empty' ) ) === 'true' ) { return false; // queue is empty } @@ -237,7 +236,7 @@ class JobQueueDB extends JobQueue { } // Check if we found a row to reserve... if ( !$row ) { - $wgMemc->set( $this->getCacheKey( 'empty' ), 'true', self::CACHE_TTL_LONG ); + $this->cache->set( $this->getCacheKey( 'empty' ), 'true', self::CACHE_TTL_LONG ); break; // nothing to do } wfIncrStats( 'job-pop' ); @@ -266,11 +265,9 @@ class JobQueueDB extends JobQueue { * @return Row|false */ protected function claimRandom( $uuid, $rand, $gte ) { - global $wgMemc; - list( $dbw, $scope ) = $this->getMasterDB(); // Check cache to see if the queue has <= OFFSET items - $tinyQueue = $wgMemc->get( $this->getCacheKey( 'small' ) ); + $tinyQueue = $this->cache->get( $this->getCacheKey( 'small' ) ); $row = false; // the row acquired $invertedDirection = false; // whether one job_random direction was already scanned @@ -311,7 +308,7 @@ class JobQueueDB extends JobQueue { ); if ( !$row ) { $tinyQueue = true; // we know the queue must have <= MAX_OFFSET rows - $wgMemc->set( $this->getCacheKey( 'small' ), 1, 30 ); + $this->cache->set( $this->getCacheKey( 'small' ), 1, 30 ); continue; // use job_random } } @@ -404,8 +401,6 @@ class JobQueueDB extends JobQueue { * @return integer Number of jobs recycled/deleted */ public function recycleAndDeleteStaleJobs() { - global $wgMemc; - $now = time(); list( $dbw, $scope ) = $this->getMasterDB(); $count = 0; // affected rows @@ -443,7 +438,7 @@ class JobQueueDB extends JobQueue { ); $count += $dbw->affectedRows(); wfIncrStats( 'job-recycle', $dbw->affectedRows() ); - $wgMemc->set( $this->getCacheKey( 'empty' ), 'false', self::CACHE_TTL_LONG ); + $this->cache->set( $this->getCacheKey( 'empty' ), 'false', self::CACHE_TTL_LONG ); } } @@ -512,16 +507,15 @@ class JobQueueDB extends JobQueue { // maintained. Having only the de-duplication registration succeed would cause // jobs to become no-ops without any actual jobs that made them redundant. list( $dbw, $scope ) = $this->getMasterDB(); - $dbw->onTransactionIdle( function() use ( $params, $key, $scope ) { - global $wgMemc; - - $timestamp = $wgMemc->get( $key ); // current last timestamp of this job + $cache = $this->cache; + $dbw->onTransactionIdle( function() use ( $cache, $params, $key, $scope ) { + $timestamp = $cache->get( $key ); // current last timestamp of this job if ( $timestamp && $timestamp >= $params['rootJobTimestamp'] ) { return true; // a newer version of this root job was enqueued } // Update the timestamp of the last root job started at the location... - return $wgMemc->set( $key, $params['rootJobTimestamp'], JobQueueDB::ROOTJOB_TTL ); + return $cache->set( $key, $params['rootJobTimestamp'], JobQueueDB::ROOTJOB_TTL ); } ); return true; @@ -551,10 +545,8 @@ class JobQueueDB extends JobQueue { * @return void */ protected function doFlushCaches() { - global $wgMemc; - foreach ( array( 'empty', 'size', 'acquiredcount' ) as $type ) { - $wgMemc->delete( $this->getCacheKey( $type ) ); + $this->cache->delete( $this->getCacheKey( $type ) ); } } -- 2.20.1