wiki.techinc.nl/maintenance/runJobs.php
Aaron Schulz d1723b7820 Disable job throttling for DuplicateJob jobs
Change-Id: I461ea9710660d061ae2da1f99f39247877332ca2
2014-04-28 23:18:25 +00:00

279 lines
8.7 KiB
PHP

<?php
/**
* Run pending jobs.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
* http://www.gnu.org/copyleft/gpl.html
*
* @file
* @ingroup Maintenance
*/
require_once __DIR__ . '/Maintenance.php';
/**
* Maintenance script that runs pending jobs.
*
* @ingroup Maintenance
*/
class RunJobs extends Maintenance {
public function __construct() {
parent::__construct();
$this->mDescription = "Run pending jobs";
$this->addOption( 'maxjobs', 'Maximum number of jobs to run', false, true );
$this->addOption( 'maxtime', 'Maximum amount of wall-clock time', false, true );
$this->addOption( 'type', 'Type of job to run', false, true );
$this->addOption( 'procs', 'Number of processes to use', false, true );
$this->addOption( 'nothrottle', 'Ignore job throttling configuration', false, false );
}
public function memoryLimit() {
if ( $this->hasOption( 'memory-limit' ) ) {
return parent::memoryLimit();
}
// Don't eat all memory on the machine if we get a bad job.
return "150M";
}
public function execute() {
if ( wfReadOnly() ) {
$this->error( "Unable to run jobs; the wiki is in read-only mode.", 1 ); // die
}
if ( $this->hasOption( 'procs' ) ) {
$procs = intval( $this->getOption( 'procs' ) );
if ( $procs < 1 || $procs > 1000 ) {
$this->error( "Invalid argument to --procs", true );
} elseif ( $procs != 1 ) {
$fc = new ForkController( $procs );
if ( $fc->start() != 'child' ) {
exit( 0 );
}
}
}
$type = $this->getOption( 'type', false );
$maxJobs = $this->getOption( 'maxjobs', false );
$maxTime = $this->getOption( 'maxtime', false );
$noThrottle = $this->hasOption( 'nothrottle' );
$startTime = time();
$group = JobQueueGroup::singleton();
// Handle any required periodic queue maintenance
$count = $group->executeReadyPeriodicTasks();
if ( $count > 0 ) {
$this->runJobsLog( "Executed $count periodic queue task(s)." );
}
$backoffs = $this->loadBackoffs(); // map of (type => UNIX expiry)
$startingBackoffs = $backoffs; // avoid unnecessary writes
$backoffExpireFunc = function ( $t ) {
return $t > time();
};
$jobsRun = 0; // counter
$flags = JobQueueGroup::USE_CACHE;
$lastTime = time(); // time since last slave check
do {
$backoffs = array_filter( $backoffs, $backoffExpireFunc );
$blacklist = $noThrottle ? array() : array_keys( $backoffs );
if ( $type === false ) {
$job = $group->pop( JobQueueGroup::TYPE_DEFAULT, $flags, $blacklist );
} elseif ( in_array( $type, $blacklist ) ) {
$job = false; // requested queue in backoff state
} else {
$job = $group->pop( $type ); // job from a single queue
}
if ( $job ) { // found a job
++$jobsRun;
$this->runJobsLog( $job->toString() . " STARTING" );
// Set timer to stop the job if too much CPU time is used
set_time_limit( $maxTime ? : 0 );
// Run the job...
wfProfileIn( __METHOD__ . '-' . get_class( $job ) );
$t = microtime( true );
try {
$status = $job->run();
$error = $job->getLastError();
} catch ( MWException $e ) {
MWExceptionHandler::rollbackMasterChangesAndLog( $e );
$status = false;
$error = get_class( $e ) . ': ' . $e->getMessage();
$e->report(); // write error to STDERR and the log
}
$timeMs = intval( ( microtime( true ) - $t ) * 1000 );
wfProfileOut( __METHOD__ . '-' . get_class( $job ) );
// Disable the timer
set_time_limit( 0 );
// Mark the job as done on success or when the job cannot be retried
if ( $status !== false || !$job->allowRetries() ) {
$group->ack( $job ); // done
}
if ( $status === false ) {
$this->runJobsLog( $job->toString() . " t=$timeMs error={$error}" );
} else {
$this->runJobsLog( $job->toString() . " t=$timeMs good" );
}
// Back off of certain jobs for a while
$ttw = $this->getBackoffTimeToWait( $job );
if ( $ttw > 0 ) {
$jType = $job->getType();
$backoffs[$jType] = isset( $backoffs[$jType] ) ? $backoffs[$jType] : 0;
$backoffs[$jType] = max( $backoffs[$jType], time() + $ttw );
}
// Break out if we hit the job count or wall time limits...
if ( $maxJobs && $jobsRun >= $maxJobs ) {
break;
} elseif ( $maxTime && ( time() - $startTime ) > $maxTime ) {
break;
}
// Don't let any of the main DB slaves get backed up
$timePassed = time() - $lastTime;
if ( $timePassed >= 5 || $timePassed < 0 ) {
wfWaitForSlaves();
$lastTime = time();
}
// Don't let any queue slaves/backups fall behind
if ( $jobsRun > 0 && ( $jobsRun % 100 ) == 0 ) {
$group->waitForBackups();
}
// Bail if near-OOM instead of in a job
$this->assertMemoryOK();
}
} while ( $job ); // stop when there are no jobs
// Sync the persistent backoffs for the next runJobs.php pass
$backoffs = array_filter( $backoffs, $backoffExpireFunc );
if ( $backoffs !== $startingBackoffs ) {
$this->syncBackoffs( $backoffs );
}
}
/**
* @param Job $job
* @return int Seconds for this runner to avoid doing more jobs of this type
* @see $wgJobBackoffThrottling
*/
private function getBackoffTimeToWait( Job $job ) {
global $wgJobBackoffThrottling;
if ( !isset( $wgJobBackoffThrottling[$job->getType()] ) ||
$job instanceof DuplicateJob // no work was done
) {
return 0; // not throttled
}
$itemsPerSecond = $wgJobBackoffThrottling[$job->getType()];
if ( $itemsPerSecond <= 0 ) {
return 0; // not throttled
}
$seconds = 0;
if ( $job->workItemCount() > 0 ) {
$seconds = floor( $job->workItemCount() / $itemsPerSecond );
$remainder = $job->workItemCount() % $itemsPerSecond;
$seconds += ( mt_rand( 1, $itemsPerSecond ) <= $remainder ) ? 1 : 0;
}
return (int)$seconds;
}
/**
* Get the previous backoff expiries from persistent storage
*
* @return array Map of (job type => backoff expiry timestamp)
*/
private function loadBackoffs() {
$section = new ProfileSection( __METHOD__ );
$backoffs = array();
$file = wfTempDir() . '/mw-runJobs-backoffs.json';
if ( is_file( $file ) ) {
$handle = fopen( $file, 'rb' );
flock( $handle, LOCK_SH );
$content = stream_get_contents( $handle );
flock( $handle, LOCK_UN );
fclose( $handle );
$backoffs = json_decode( $content, true ) ? : array();
}
return $backoffs;
}
/**
* Merge the current backoff expiries from persistent storage
*
* @param array $backoffs Map of (job type => backoff expiry timestamp)
*/
private function syncBackoffs( array $backoffs ) {
$section = new ProfileSection( __METHOD__ );
$file = wfTempDir() . '/mw-runJobs-backoffs.json';
$handle = fopen( $file, 'wb+' );
flock( $handle, LOCK_EX );
$content = stream_get_contents( $handle );
$cBackoffs = json_decode( $content, true ) ? : array();
foreach ( $backoffs as $type => $timestamp ) {
$cBackoffs[$type] = isset( $cBackoffs[$type] ) ? $cBackoffs[$type] : 0;
$cBackoffs[$type] = max( $cBackoffs[$type], $backoffs[$type] );
}
ftruncate( $handle, 0 );
fwrite( $handle, json_encode( $backoffs ) );
flock( $handle, LOCK_UN );
fclose( $handle );
}
/**
* Make sure that this script is not too close to the memory usage limit.
* It is better to die in between jobs than OOM right in the middle of one.
* @throws MWException
*/
private function assertMemoryOK() {
static $maxBytes = null;
if ( $maxBytes === null ) {
$m = array();
if ( preg_match( '!^(\d+)(k|m|g|)$!i', ini_get( 'memory_limit' ), $m ) ) {
list( , $num, $unit ) = $m;
$conv = array( 'g' => 1073741824, 'm' => 1048576, 'k' => 1024, '' => 1 );
$maxBytes = $num * $conv[strtolower( $unit )];
} else {
$maxBytes = 0;
}
}
$usedBytes = memory_get_usage();
if ( $maxBytes && $usedBytes >= 0.95 * $maxBytes ) {
throw new MWException( "Detected excessive memory usage ($usedBytes/$maxBytes)." );
}
}
/**
* Log the job message
* @param string $msg The message to log
*/
private function runJobsLog( $msg ) {
$this->output( wfTimestamp( TS_DB ) . " $msg\n" );
wfDebugLog( 'runJobs', $msg );
}
}
$maintClass = "RunJobs";
require_once RUN_MAINTENANCE_IF_MAIN;