BagOStuff: Optionally log duplicate key lookups

[lhc/web/wiklou.git] / includes / objectcache / ObjectCache.php

diff --git a/includes/objectcache/ObjectCache.php b/includes/objectcache/ObjectCache.php
index 217b61f..bf152b6 100644 (file)
--- a/includes/objectcache/ObjectCache.php
+++ b/includes/objectcache/ObjectCache.php
@@ -44,12 +44,13 @@ use MediaWiki\Logger\LoggerFactory;
  *
  * - ObjectCache::getMainWANInstance()
  *   Purpose: Memory cache.
- *   Stored in the local data-center's main cache (uses different cache keys).
- *   Delete events are broadcasted to other DCs. See WANObjectCache for details.
+ *   Stored in the local data-center's main cache (keyspace different from local-cluster cache).
+ *   Delete events are broadcasted to other DCs main cache. See WANObjectCache for details.
  *
  * - ObjectCache::getLocalServerInstance( $fallbackType )
  *   Purpose: Memory cache for very hot keys.
- *   Stored only on the individual web server (often EmptyBagOStuff in CLI mode).
+ *   Stored only on the individual web server (typically APC for web requests,
+ *   and EmptyBagOStuff in CLI mode).
  *   Not replicated to the other servers.
  *
  * - ObjectCache::getLocalClusterInstance()
@@ -62,7 +63,7 @@ use MediaWiki\Logger\LoggerFactory;
  *   Purpose: Ephemeral global storage.
  *   Stored centrally within the primary data-center.
  *   Changes are applied there first and replicated to other DCs (best-effort).
- *   To retrieve the latest value (e.g. not from a slave), use BagOStuff:READ_LATEST.
+ *   To retrieve the latest value (e.g. not from a slave), use BagOStuff::READ_LATEST.
  *   This store may be subject to LRU style evictions.
  *
  * - ObjectCache::getInstance( $cacheType )
@@ -77,9 +78,9 @@ use MediaWiki\Logger\LoggerFactory;
  */
 class ObjectCache {
        /** @var BagOStuff[] Map of (id => BagOStuff) */
-       public static $instances = array();
+       public static $instances = [];
        /** @var WANObjectCache[] Map of (id => WANObjectCache) */
-       public static $wanInstances = array();
+       public static $wanInstances = [];
 
        /**
         * Get a cached instance of the specified type of cache object.
@@ -138,19 +139,14 @@ class ObjectCache {
         * @return string
         */
        public static function getDefaultKeyspace() {
-               global $wgCachePrefix, $wgDBname, $wgDBprefix;
+               global $wgCachePrefix;
 
                $keyspace = $wgCachePrefix;
                if ( is_string( $keyspace ) && $keyspace !== '' ) {
                        return $keyspace;
                }
 
-               $keyspace = $wgDBname;
-               if ( is_string( $wgDBprefix ) && $wgDBprefix !== '' ) {
-                       $keyspace .= '-' . $wgDBprefix;
-               }
-
-               return $keyspace;
+               return wfWikiID();
        }
 
        /**
@@ -178,11 +174,13 @@ class ObjectCache {
                } elseif ( isset( $params['class'] ) ) {
                        $class = $params['class'];
                        // Automatically set the 'async' update handler
-                       if ( $class === 'MultiWriteBagOStuff' ) {
-                               $params['asyncHandler'] = isset( $params['asyncHandler'] )
-                                       ? $params['asyncHandler']
-                                       : 'DeferredUpdates::addCallableUpdate';
-                       }
+                       $params['asyncHandler'] = isset( $params['asyncHandler'] )
+                               ? $params['asyncHandler']
+                               : 'DeferredUpdates::addCallableUpdate';
+                       // Enable reportDupes by default
+                       $params['reportDupes'] = isset( $params['reportDupes'] )
+                               ? $params['reportDupes']
+                               : true;
                        // Do b/c logic for MemcachedBagOStuff
                        if ( is_subclass_of( $class, 'MemcachedBagOStuff' ) ) {
                                if ( !isset( $params['servers'] ) ) {
@@ -221,7 +219,7 @@ class ObjectCache {
         */
        public static function newAnything( $params ) {
                global $wgMainCacheType, $wgMessageCacheType, $wgParserCacheType;
-               $candidates = array( $wgMainCacheType, $wgMessageCacheType, $wgParserCacheType );
+               $candidates = [ $wgMainCacheType, $wgMessageCacheType, $wgParserCacheType ];
                foreach ( $candidates as $candidate ) {
                        if ( $candidate !== CACHE_NONE && $candidate !== CACHE_ANYTHING ) {
                                return self::getInstance( $candidate );
@@ -271,10 +269,8 @@ class ObjectCache {
         * @return BagOStuff
         * @deprecated 1.27
         */
-       public static function newAccelerator( $params = array(), $fallback = null ) {
+       public static function newAccelerator( $params = [], $fallback = null ) {
                if ( $fallback === null ) {
-                       // The is_array check here is needed because in PHP 5.3:
-                       // $a = 'hash'; isset( $params['fallback'] ); yields true
                        if ( is_array( $params ) && isset( $params['fallback'] ) ) {
                                $fallback = $params['fallback'];
                        } elseif ( !is_array( $params ) ) {
@@ -367,7 +363,7 @@ class ObjectCache {
         * Clear all the cached instances.
         */
        public static function clear() {
-               self::$instances = array();
-               self::$wanInstances = array();
+               self::$instances = [];
+               self::$wanInstances = [];
        }
 }