Merge "Use Xml::element instead of Html::element for empty elements"

[lhc/web/wiklou.git] / includes / db / LoadBalancer.php

diff --git a/includes/db/LoadBalancer.php b/includes/db/LoadBalancer.php
index b3f9210..db4ed60 100644 (file)
--- a/includes/db/LoadBalancer.php
+++ b/includes/db/LoadBalancer.php
@@ -43,7 +43,7 @@ class LoadBalancer {
        private $mLoadMonitorClass, $mLoadMonitor;
 
        /**
-        * @param array $params with keys:
+        * @param array $params Array with keys:
         *   servers           Required. Array of server info structures.
         *   loadMonitor       Name of a class used to fetch server lag and load.
         * @throws MWException
@@ -331,17 +331,23 @@ class LoadBalancer {
        /**
         * Set the master wait position and wait for ALL slaves to catch up to it
         * @param DBMasterPos $pos
+        * @param int $timeout Max seconds to wait; default is mWaitTimeout
+        * @return bool Success (able to connect and no timeouts reached)
         */
-       public function waitForAll( $pos ) {
+       public function waitForAll( $pos, $timeout = null ) {
                wfProfileIn( __METHOD__ );
                $this->mWaitForPos = $pos;
                $serverCount = count( $this->mServers );
+
+               $ok = true;
                for ( $i = 1; $i < $serverCount; $i++ ) {
                        if ( $this->mLoads[$i] > 0 ) {
-                               $this->doWait( $i, true );
+                               $ok = $this->doWait( $i, true, $timeout ) && $ok;
                        }
                }
                wfProfileOut( __METHOD__ );
+
+               return $ok;
        }
 
        /**
@@ -363,11 +369,12 @@ class LoadBalancer {
 
        /**
         * Wait for a given slave to catch up to the master pos stored in $this
-        * @param int $index
-        * @param bool $open
+        * @param int $index Server index
+        * @param bool $open Check the server even if a new connection has to be made
+        * @param int $timeout Max seconds to wait; default is mWaitTimeout
         * @return bool
         */
-       protected function doWait( $index, $open = false ) {
+       protected function doWait( $index, $open = false, $timeout = null ) {
                # Find a connection to wait on
                $conn = $this->getAnyOpenConnection( $index );
                if ( !$conn ) {
@@ -386,7 +393,8 @@ class LoadBalancer {
                }
 
                wfDebug( __METHOD__ . ": Waiting for slave #$index to catch up...\n" );
-               $result = $conn->masterPosWait( $this->mWaitForPos, $this->mWaitTimeout );
+               $timeout = $timeout ?: $this->mWaitTimeout;
+               $result = $conn->masterPosWait( $this->mWaitForPos, $timeout );
 
                if ( $result == -1 || is_null( $result ) ) {
                        # Timed out waiting for slave, use master instead
@@ -948,6 +956,14 @@ class LoadBalancer {
                }
        }
 
+       /**
+        * @return bool Whether a master connection is already open
+        * @since 1.24
+        */
+       function hasMasterConnection() {
+               return $this->isOpen( $this->getWriterIndex() );
+       }
+
        /**
         * Determine if there are any pending changes that need to be rolled back
         * or committed.
@@ -1048,8 +1064,22 @@ class LoadBalancer {
                $maxLag = -1;
                $host = '';
                $maxIndex = 0;
-               if ( $this->getServerCount() > 1 ) { // no replication = no lag
+
+               if ( $this->getServerCount() <= 1 ) { // no replication = no lag
+                       return array( $host, $maxLag, $maxIndex );
+               }
+
+               // Try to get the max lag info from the server cache
+               $key = 'loadbalancer:maxlag:cluster:' . $this->mServers[0]['host'];
+               $cache = ObjectCache::newAccelerator( array(), 'hash' );
+               $maxLagInfo = $cache->get( $key ); // (host, lag, index)
+
+               // Fallback to connecting to each slave and getting the lag
+               if ( !$maxLagInfo ) {
                        foreach ( $this->mServers as $i => $conn ) {
+                               if ( $i == $this->getWriterIndex() ) {
+                                       continue; // nothing to check
+                               }
                                $conn = false;
                                if ( $wiki === false ) {
                                        $conn = $this->getAnyOpenConnection( $i );
@@ -1067,9 +1097,11 @@ class LoadBalancer {
                                        $maxIndex = $i;
                                }
                        }
+                       $maxLagInfo = array( $host, $maxLag, $maxIndex );
+                       $cache->set( $key, $maxLagInfo, 5 );
                }
 
-               return array( $host, $maxLag, $maxIndex );
+               return $maxLagInfo;
        }
 
        /**