X-Git-Url: https://git.heureux-cyclage.org/?p=lhc%2Fweb%2Fwiklou.git;a=blobdiff_plain;f=includes%2Flibs%2Flockmanager%2FQuorumLockManager.php;h=83dcc6be56edc0e7382da05eb9fac139a23de85c;hp=950b283670bf44d5b96d503fff5a81ddcafa781b;hb=fa0f6f34972c0e0f4aac24a03b3efdfc45f256f6;hpb=316509d9083b4b86dea516b640a7e11dc3924b7c

diff --git a/includes/libs/lockmanager/QuorumLockManager.php b/includes/libs/lockmanager/QuorumLockManager.php
index 950b283670..83dcc6be56 100644
--- a/includes/libs/lockmanager/QuorumLockManager.php
+++ b/includes/libs/lockmanager/QuorumLockManager.php
@@ -38,7 +38,7 @@ abstract class QuorumLockManager extends LockManager {
 	final protected function doLockByType( array $pathsByType ) {
 		$status = StatusValue::newGood();
 
-		$pathsToLock = []; // (bucket => type => paths)
+		$pathsByTypeByBucket = []; // (bucket => type => paths)
 		// Get locks that need to be acquired (buckets => locks)...
 		foreach ( $pathsByType as $type => $paths ) {
 			foreach ( $paths as $path ) {
@@ -46,23 +46,27 @@ abstract class QuorumLockManager extends LockManager {
 					++$this->locksHeld[$path][$type];
 				} else {
 					$bucket = $this->getBucketFromPath( $path );
-					$pathsToLock[$bucket][$type][] = $path;
+					$pathsByTypeByBucket[$bucket][$type][] = $path;
 				}
 			}
 		}
 
+		// Acquire locks in each bucket in bucket order to reduce contention. Any blocking
+		// mutexes during the acquisition step will not involve circular waiting on buckets.
+		ksort( $pathsByTypeByBucket );
+
 		$lockedPaths = []; // files locked in this attempt (type => paths)
 		// Attempt to acquire these locks...
-		foreach ( $pathsToLock as $bucket => $pathsToLockByType ) {
+		foreach ( $pathsByTypeByBucket as $bucket => $bucketPathsByType ) {
 			// Try to acquire the locks for this bucket
-			$status->merge( $this->doLockingRequestBucket( $bucket, $pathsToLockByType ) );
+			$status->merge( $this->doLockingRequestBucket( $bucket, $bucketPathsByType ) );
 			if ( !$status->isOK() ) {
 				$status->merge( $this->doUnlockByType( $lockedPaths ) );
 
 				return $status;
 			}
 			// Record these locks as active
-			foreach ( $pathsToLockByType as $type => $paths ) {
+			foreach ( $bucketPathsByType as $type => $paths ) {
 				foreach ( $paths as $path ) {
 					$this->locksHeld[$path][$type] = 1; // locked
 					// Keep track of what locks were made in this attempt
@@ -77,7 +81,7 @@ abstract class QuorumLockManager extends LockManager {
 	protected function doUnlockByType( array $pathsByType ) {
 		$status = StatusValue::newGood();
 
-		$pathsToUnlock = []; // (bucket => type => paths)
+		$pathsByTypeByBucket = []; // (bucket => type => paths)
 		foreach ( $pathsByType as $type => $paths ) {
 			foreach ( $paths as $path ) {
 				if ( !isset( $this->locksHeld[$path][$type] ) ) {
@@ -88,7 +92,7 @@ abstract class QuorumLockManager extends LockManager {
 					if ( $this->locksHeld[$path][$type] <= 0 ) {
 						unset( $this->locksHeld[$path][$type] );
 						$bucket = $this->getBucketFromPath( $path );
-						$pathsToUnlock[$bucket][$type][] = $path;
+						$pathsByTypeByBucket[$bucket][$type][] = $path;
 					}
 					if ( $this->locksHeld[$path] === [] ) {
 						unset( $this->locksHeld[$path] ); // no SH or EX locks left for key
@@ -99,8 +103,8 @@ abstract class QuorumLockManager extends LockManager {
 
 		// Remove these specific locks if possible, or at least release
 		// all locks once this process is currently not holding any locks.
-		foreach ( $pathsToUnlock as $bucket => $pathsToUnlockByType ) {
-			$status->merge( $this->doUnlockingRequestBucket( $bucket, $pathsToUnlockByType ) );
+		foreach ( $pathsByTypeByBucket as $bucket => $bucketPathsByType ) {
+			$status->merge( $this->doUnlockingRequestBucket( $bucket, $bucketPathsByType ) );
 		}
 		if ( $this->locksHeld === [] ) {
 			$status->merge( $this->releaseAllLocks() );
@@ -148,7 +152,7 @@ abstract class QuorumLockManager extends LockManager {
 	 * This is all or nothing; if any key is already pledged then this totally fails.
 	 *
 	 * @param int $bucket
-	 * @param callable $callback Pledge method taking a server name and yeilding a StatusValue
+	 * @param callable $callback Pledge method taking a server name and yielding a StatusValue
 	 * @return StatusValue
 	 */
 	final protected function collectPledgeQuorum( $bucket, callable $callback ) {
@@ -190,7 +194,7 @@ abstract class QuorumLockManager extends LockManager {
 	 * Attempt to release pledges with the peers for a bucket
 	 *
 	 * @param int $bucket
-	 * @param callable $callback Pledge method taking a server name and yeilding a StatusValue
+	 * @param callable $callback Pledge method taking a server name and yielding a StatusValue
 	 * @return StatusValue
 	 */
 	final protected function releasePledges( $bucket, callable $callback ) {