X-Git-Url: https://git.heureux-cyclage.org/?p=lhc%2Fweb%2Fwiklou.git;a=blobdiff_plain;f=includes%2Fdb%2FLoadBalancer.php;h=2ea2487501a88447cbb0adb599e0c8891e9b1978;hp=d9584e147bae96b0eb3081ef5b1ab2e9d8c7aa25;hb=35d9ad550f2f443455b3b76495d9cebfafdfaf37;hpb=5efccbed2a8db2a2b210d6116bd608da01342030

diff --git a/includes/db/LoadBalancer.php b/includes/db/LoadBalancer.php
index d9584e147b..2ea2487501 100644
--- a/includes/db/LoadBalancer.php
+++ b/includes/db/LoadBalancer.php
@@ -214,7 +214,7 @@ class LoadBalancer {
 	 * @return bool|int|string
 	 */
 	public function getReaderIndex( $group = false, $wiki = false ) {
-		global $wgReadOnly, $wgDBtype;
+		global $wgDBtype;
 
 		# @todo FIXME: For now, only go through all this for mysql databases
 		if ( $wgDBtype != 'mysql' ) {
@@ -258,7 +258,7 @@ class LoadBalancer {
 		# meets our criteria
 		$currentLoads = $nonErrorLoads;
 		while ( count( $currentLoads ) ) {
-			if ( $wgReadOnly || $this->mAllowLagged || $laggedSlaveMode ) {
+			if ( $this->mAllowLagged || $laggedSlaveMode ) {
 				$i = ArrayUtils::pickRandom( $currentLoads );
 			} else {
 				$i = false;
@@ -277,8 +277,6 @@ class LoadBalancer {
 				if ( $i === false && count( $currentLoads ) != 0 ) {
 					# All slaves lagged. Switch to read-only mode
 					wfDebugLog( 'replication', "All slaves lagged. Switch to read-only mode" );
-					$wgReadOnly = 'The database has been automatically locked ' .
-						'while the slave database servers catch up to the master';
 					$i = ArrayUtils::pickRandom( $currentLoads );
 					$laggedSlaveMode = true;
 				}
@@ -330,6 +328,10 @@ class LoadBalancer {
 			}
 			if ( $this->mReadIndex <= 0 && $this->mLoads[$i] > 0 && $group === false ) {
 				$this->mReadIndex = $i;
+				# Record if the generic reader index is in "lagged slave" mode
+				if ( $laggedSlaveMode ) {
+					$this->mLaggedSlaveMode = true;
+				}
 			}
 			$serverName = $this->getServerName( $i );
 			wfDebug( __METHOD__ . ": using server $serverName for group '$group'\n" );
@@ -356,6 +358,37 @@ class LoadBalancer {
 		}
 	}
 
+	/**
+	 * Set the master wait position and wait for a "generic" slave to catch up to it
+	 *
+	 * This can be used a faster proxy for waitForAll()
+	 *
+	 * @param DBMasterPos $pos
+	 * @param int $timeout Max seconds to wait; default is mWaitTimeout
+	 * @return bool Success (able to connect and no timeouts reached)
+	 * @since 1.26
+	 */
+	public function waitForOne( $pos, $timeout = null ) {
+		$this->mWaitForPos = $pos;
+
+		$i = $this->mReadIndex;
+		if ( $i <= 0 ) {
+			// Pick a generic slave if there isn't one yet
+			$readLoads = $this->mLoads;
+			unset( $readLoads[$this->getWriterIndex()] ); // slaves only
+			$readLoads = array_filter( $readLoads ); // with non-zero load
+			$i = ArrayUtils::pickRandom( $readLoads );
+		}
+
+		if ( $i > 0 ) {
+			$ok = $this->doWait( $i, true, $timeout );
+		} else {
+			$ok = true; // no applicable loads
+		}
+
+		return $ok;
+	}
+
 	/**
 	 * Set the master wait position and wait for ALL slaves to catch up to it
 	 * @param DBMasterPos $pos
@@ -812,8 +845,9 @@ class LoadBalancer {
 
 	/**
 	 * @return int
+	 * @since 1.26
 	 */
-	private function getWriterIndex() {
+	public function getWriterIndex() {
 		return 0;
 	}
 
@@ -1096,9 +1130,12 @@ class LoadBalancer {
 	}
 
 	/**
-	 * @return bool
+	 * @return bool Whether the generic connection for reads is highly "lagged"
 	 */
 	public function getLaggedSlaveMode() {
+		# Get a generic reader connection
+		$this->getConnection( DB_SLAVE );
+
 		return $this->mLaggedSlaveMode;
 	}
 
@@ -1236,49 +1273,3 @@ class LoadBalancer {
 		$this->mProcCache->clear( 'slave_lag' );
 	}
 }
-
-/**
- * Helper class to handle automatically marking connections as reusable (via RAII pattern)
- * as well handling deferring the actual network connection until the handle is used
- *
- * @ingroup Database
- * @since 1.22
- */
-class DBConnRef implements IDatabase {
-	/** @var LoadBalancer */
-	private $lb;
-
-	/** @var DatabaseBase|null */
-	private $conn;
-
-	/** @var array|null */
-	private $params;
-
-	/**
-	 * @param LoadBalancer $lb
-	 * @param DatabaseBase|array $conn Connection or (server index, group, wiki ID) array
-	 */
-	public function __construct( LoadBalancer $lb, $conn ) {
-		$this->lb = $lb;
-		if ( $conn instanceof DatabaseBase ) {
-			$this->conn = $conn;
-		} else {
-			$this->params = $conn;
-		}
-	}
-
-	public function __call( $name, $arguments ) {
-		if ( $this->conn === null ) {
-			list( $db, $groups, $wiki ) = $this->params;
-			$this->conn = $this->lb->getConnection( $db, $groups, $wiki );
-		}
-
-		return call_user_func_array( array( $this->conn, $name ), $arguments );
-	}
-
-	public function __destruct() {
-		if ( $this->conn !== null ) {
-			$this->lb->reuseConnection( $this->conn );
-		}
-	}
-}