+++ /dev/null
-<?php
-/**
- * Advanced generator of database load balancing objects for wiki farms
- *
- * @file
- * @ingroup Database
- */
-
-
-/**
- * A multi-wiki, multi-master factory for Wikimedia and similar installations.
- * Ignores the old configuration globals
- *
- * Configuration:
- * sectionsByDB A map of database names to section names
- *
- * sectionLoads A 2-d map. For each section, gives a map of server names to load ratios.
- * For example: array( 'section1' => array( 'db1' => 100, 'db2' => 100 ) )
- *
- * serverTemplate A server info associative array as documented for $wgDBservers. The host,
- * hostName and load entries will be overridden.
- *
- * groupLoadsBySection A 3-d map giving server load ratios for each section and group. For example:
- * array( 'section1' => array( 'group1' => array( 'db1' => 100, 'db2' => 100 ) ) )
- *
- * groupLoadsByDB A 3-d map giving server load ratios by DB name.
- *
- * hostsByName A map of hostname to IP address.
- *
- * externalLoads A map of external storage cluster name to server load map
- *
- * externalTemplateOverrides A set of server info keys overriding serverTemplate for external storage
- *
- * templateOverridesByServer A 2-d map overriding serverTemplate and externalTemplateOverrides on a
- * server-by-server basis. Applies to both core and external storage.
- *
- * templateOverridesByCluster A 2-d map overriding the server info by external storage cluster
- *
- * masterTemplateOverrides An override array for all master servers.
- *
- * readOnlyBySection A map of section name to read-only message. Missing or false for read/write.
- *
- * @ingroup Database
- */
-class LBFactory_Multi extends LBFactory {
- // Required settings
- var $sectionsByDB, $sectionLoads, $serverTemplate;
- // Optional settings
- var $groupLoadsBySection = array(), $groupLoadsByDB = array(), $hostsByName = array();
- var $externalLoads = array(), $externalTemplateOverrides, $templateOverridesByServer;
- var $templateOverridesByCluster, $masterTemplateOverrides, $readOnlyBySection = array();
- // Other stuff
- var $conf, $mainLBs = array(), $extLBs = array();
- var $lastWiki, $lastSection;
-
- function __construct( $conf ) {
- $this->chronProt = new ChronologyProtector;
- $this->conf = $conf;
- $required = array( 'sectionsByDB', 'sectionLoads', 'serverTemplate' );
- $optional = array( 'groupLoadsBySection', 'groupLoadsByDB', 'hostsByName',
- 'externalLoads', 'externalTemplateOverrides', 'templateOverridesByServer',
- 'templateOverridesByCluster', 'masterTemplateOverrides',
- 'readOnlyBySection' );
-
- foreach ( $required as $key ) {
- if ( !isset( $conf[$key] ) ) {
- throw new MWException( __CLASS__.": $key is required in configuration" );
- }
- $this->$key = $conf[$key];
- }
-
- foreach ( $optional as $key ) {
- if ( isset( $conf[$key] ) ) {
- $this->$key = $conf[$key];
- }
- }
-
- // Check for read-only mode
- $section = $this->getSectionForWiki();
- if ( !empty( $this->readOnlyBySection[$section] ) ) {
- global $wgReadOnly;
- $wgReadOnly = $this->readOnlyBySection[$section];
- }
- }
-
- function getSectionForWiki( $wiki = false ) {
- if ( $this->lastWiki === $wiki ) {
- return $this->lastSection;
- }
- list( $dbName, ) = $this->getDBNameAndPrefix( $wiki );
- if ( isset( $this->sectionsByDB[$dbName] ) ) {
- $section = $this->sectionsByDB[$dbName];
- } else {
- $section = 'DEFAULT';
- }
- $this->lastSection = $section;
- $this->lastWiki = $wiki;
- return $section;
- }
-
- function newMainLB( $wiki = false ) {
- list( $dbName, ) = $this->getDBNameAndPrefix( $wiki );
- $section = $this->getSectionForWiki( $wiki );
- $groupLoads = array();
- if ( isset( $this->groupLoadsByDB[$dbName] ) ) {
- $groupLoads = $this->groupLoadsByDB[$dbName];
- }
- if ( isset( $this->groupLoadsBySection[$section] ) ) {
- $groupLoads = array_merge_recursive( $groupLoads, $this->groupLoadsBySection[$section] );
- }
- return $this->newLoadBalancer( $this->serverTemplate, $this->sectionLoads[$section], $groupLoads );
- }
-
- function getMainLB( $wiki = false ) {
- $section = $this->getSectionForWiki( $wiki );
- if ( !isset( $this->mainLBs[$section] ) ) {
- $lb = $this->newMainLB( $wiki, $section );
- $this->chronProt->initLB( $lb );
- $lb->parentInfo( array( 'id' => "main-$section" ) );
- $this->mainLBs[$section] = $lb;
- }
- return $this->mainLBs[$section];
- }
-
- function newExternalLB( $cluster, $wiki = false ) {
- if ( !isset( $this->externalLoads[$cluster] ) ) {
- throw new MWException( __METHOD__.": Unknown cluster \"$cluster\"" );
- }
- $template = $this->serverTemplate;
- if ( isset( $this->externalTemplateOverrides ) ) {
- $template = $this->externalTemplateOverrides + $template;
- }
- if ( isset( $this->templateOverridesByCluster[$cluster] ) ) {
- $template = $this->templateOverridesByCluster[$cluster] + $template;
- }
- return $this->newLoadBalancer( $template, $this->externalLoads[$cluster], array() );
- }
-
- function &getExternalLB( $cluster, $wiki = false ) {
- if ( !isset( $this->extLBs[$cluster] ) ) {
- $this->extLBs[$cluster] = $this->newExternalLB( $cluster, $wiki );
- $this->extLBs[$cluster]->parentInfo( array( 'id' => "ext-$cluster" ) );
- }
- return $this->extLBs[$cluster];
- }
-
- /**
- * Make a new load balancer object based on template and load array
- */
- function newLoadBalancer( $template, $loads, $groupLoads ) {
- global $wgMasterWaitTimeout;
- $servers = $this->makeServerArray( $template, $loads, $groupLoads );
- $lb = new LoadBalancer( array(
- 'servers' => $servers,
- 'masterWaitTimeout' => $wgMasterWaitTimeout
- ));
- return $lb;
- }
-
- /**
- * Make a server array as expected by LoadBalancer::__construct, using a template and load array
- */
- function makeServerArray( $template, $loads, $groupLoads ) {
- $servers = array();
- $master = true;
- $groupLoadsByServer = $this->reindexGroupLoads( $groupLoads );
- foreach ( $groupLoadsByServer as $server => $stuff ) {
- if ( !isset( $loads[$server] ) ) {
- $loads[$server] = 0;
- }
- }
- foreach ( $loads as $serverName => $load ) {
- $serverInfo = $template;
- if ( $master ) {
- $serverInfo['master'] = true;
- if ( isset( $this->masterTemplateOverrides ) ) {
- $serverInfo = $this->masterTemplateOverrides + $serverInfo;
- }
- $master = false;
- }
- if ( isset( $this->templateOverridesByServer[$serverName] ) ) {
- $serverInfo = $this->templateOverridesByServer[$serverName] + $serverInfo;
- }
- if ( isset( $groupLoadsByServer[$serverName] ) ) {
- $serverInfo['groupLoads'] = $groupLoadsByServer[$serverName];
- }
- if ( isset( $this->hostsByName[$serverName] ) ) {
- $serverInfo['host'] = $this->hostsByName[$serverName];
- } else {
- $serverInfo['host'] = $serverName;
- }
- $serverInfo['hostName'] = $serverName;
- $serverInfo['load'] = $load;
- $servers[] = $serverInfo;
- }
- return $servers;
- }
-
- /**
- * Take a group load array indexed by group then server, and reindex it by server then group
- */
- function reindexGroupLoads( $groupLoads ) {
- $reindexed = array();
- foreach ( $groupLoads as $group => $loads ) {
- foreach ( $loads as $server => $load ) {
- $reindexed[$server][$group] = $load;
- }
- }
- return $reindexed;
- }
-
- /**
- * Get the database name and prefix based on the wiki ID
- */
- function getDBNameAndPrefix( $wiki = false ) {
- if ( $wiki === false ) {
- global $wgDBname, $wgDBprefix;
- return array( $wgDBname, $wgDBprefix );
- } else {
- return wfSplitWikiID( $wiki );
- }
- }
-
- /**
- * Execute a function for each tracked load balancer
- * The callback is called with the load balancer as the first parameter,
- * and $params passed as the subsequent parameters.
- */
- function forEachLB( $callback, $params = array() ) {
- foreach ( $this->mainLBs as $lb ) {
- call_user_func_array( $callback, array_merge( array( $lb ), $params ) );
- }
- foreach ( $this->extLBs as $lb ) {
- call_user_func_array( $callback, array_merge( array( $lb ), $params ) );
- }
- }
-
- function shutdown() {
- foreach ( $this->mainLBs as $lb ) {
- $this->chronProt->shutdownLB( $lb );
- }
- $this->chronProt->shutdown();
- $this->commitMasterChanges();
- }
-}
scripts.mit.edu / autoinstallsdev / mediawiki.git / blobdiff