X-Git-Url: https://git.heureux-cyclage.org/?a=blobdiff_plain;f=includes%2Fdeferred%2FLinksUpdate.php;h=07b56144246be90814696889b8a52ac147ff4b24;hb=b746001c6659413c70b12651075872532de6130c;hp=4215ed09b1f4bf4bcebff34c431c86d3f1a9bafd;hpb=b5906606e1aa1a795231fb813b766818b1dd6c25;p=lhc%2Fweb%2Fwiklou.git

diff --git a/includes/deferred/LinksUpdate.php b/includes/deferred/LinksUpdate.php
index 4215ed09b1..07b5614424 100644
--- a/includes/deferred/LinksUpdate.php
+++ b/includes/deferred/LinksUpdate.php
@@ -21,9 +21,11 @@
  */
 
 /**
- * See docs/deferred.txt
+ * Class the manages updates of *_link tables as well as similar extension-managed tables
+ *
+ * @note: LinksUpdate is managed by DeferredUpdates::execute(). Do not run this in a transaction.
  *
- * @todo document (e.g. one-sentence top-level class description).
+ * See docs/deferred.txt
  */
 class LinksUpdate extends SqlDataUpdate implements EnqueueableDataUpdate {
 	// @todo make members protected, but make sure extensions don't break
@@ -55,6 +57,9 @@ class LinksUpdate extends SqlDataUpdate implements EnqueueableDataUpdate {
 	/** @var array Map of language codes to titles */
 	public $mInterlangs;
 
+	/** @var array 2-D map of (prefix => DBK => 1) */
+	public $mInterwikis;
+
 	/** @var array Map of arbitrary name to value */
 	public $mProperties;
 
@@ -88,7 +93,8 @@ class LinksUpdate extends SqlDataUpdate implements EnqueueableDataUpdate {
 	 * @throws MWException
 	 */
 	function __construct( Title $title, ParserOutput $parserOutput, $recursive = true ) {
-		parent::__construct( false ); // no implicit transaction
+		// Implicit transactions are disabled as they interfere with batching
+		parent::__construct( false );
 
 		$this->mTitle = $title;
 		$this->mId = $title->getArticleID( Title::GAID_FOR_UPDATE );
@@ -138,16 +144,46 @@ class LinksUpdate extends SqlDataUpdate implements EnqueueableDataUpdate {
 
 	/**
 	 * Update link tables with outgoing links from an updated article
+	 *
+	 * @note: this is managed by DeferredUpdates::execute(). Do not run this in a transaction.
 	 */
 	public function doUpdate() {
+		// Make sure all links update threads see the changes of each other.
+		// This handles the case when updates have to batched into several COMMITs.
+		$scopedLock = self::acquirePageLock( $this->mDb, $this->mId );
+
 		Hooks::run( 'LinksUpdate', [ &$this ] );
 		$this->doIncrementalUpdate();
 
-		$this->mDb->onTransactionIdle( function() {
+		$this->mDb->onTransactionIdle( function() use ( &$scopedLock ) {
 			Hooks::run( 'LinksUpdateComplete', [ &$this ] );
+			// Release the lock *after* the final COMMIT for correctness
+			ScopedCallback::consume( $scopedLock );
 		} );
 	}
 
+	/**
+	 * Acquire a lock for performing link table updates for a page on a DB
+	 *
+	 * @param IDatabase $dbw
+	 * @param integer $pageId
+	 * @return ScopedCallback|null Returns null on failure
+	 * @throws RuntimeException
+	 * @since 1.27
+	 */
+	public static function acquirePageLock( IDatabase $dbw, $pageId ) {
+		$scopedLock = $dbw->getScopedLockAndFlush(
+			"LinksUpdate:pageid:$pageId",
+			__METHOD__,
+			15
+		);
+		if ( !$scopedLock ) {
+			throw new RuntimeException( "Could not acquire lock on page #$pageId." );
+		}
+
+		return $scopedLock;
+	}
+
 	protected function doIncrementalUpdate() {
 		# Page links
 		$existing = $this->getExistingLinks();
@@ -157,7 +193,6 @@ class LinksUpdate extends SqlDataUpdate implements EnqueueableDataUpdate {
 
 		# Image links
 		$existing = $this->getExistingImages();
-
 		$imageDeletes = $this->getImageDeletions( $existing );
 		$this->incrTableUpdate( 'imagelinks', 'il', $imageDeletes,
 			$this->getImageInsertions( $existing ) );
@@ -188,9 +223,7 @@ class LinksUpdate extends SqlDataUpdate implements EnqueueableDataUpdate {
 
 		# Category links
 		$existing = $this->getExistingCategories();
-
 		$categoryDeletes = $this->getCategoryDeletions( $existing );
-
 		$this->incrTableUpdate( 'categorylinks', 'cl', $categoryDeletes,
 			$this->getCategoryInsertions( $existing ) );
 
@@ -202,9 +235,7 @@ class LinksUpdate extends SqlDataUpdate implements EnqueueableDataUpdate {
 
 		# Page properties
 		$existing = $this->getExistingProperties();
-
 		$propertiesDeletes = $this->getPropertyDeletions( $existing );
-
 		$this->incrTableUpdate( 'page_props', 'pp', $propertiesDeletes,
 			$this->getPropertyInsertions( $existing ) );
 
@@ -304,44 +335,71 @@ class LinksUpdate extends SqlDataUpdate implements EnqueueableDataUpdate {
 	 * @param array $deletions
 	 * @param array $insertions Rows to insert
 	 */
-	function incrTableUpdate( $table, $prefix, $deletions, $insertions ) {
-		if ( $table == 'page_props' ) {
+	private function incrTableUpdate( $table, $prefix, $deletions, $insertions ) {
+		$bSize = RequestContext::getMain()->getConfig()->get( 'UpdateRowsPerQuery' );
+
+		if ( $table === 'page_props' ) {
 			$fromField = 'pp_page';
 		} else {
 			$fromField = "{$prefix}_from";
 		}
-		$where = [ $fromField => $this->mId ];
-		if ( $table == 'pagelinks' || $table == 'templatelinks' || $table == 'iwlinks' ) {
-			if ( $table == 'iwlinks' ) {
-				$baseKey = 'iwl_prefix';
-			} else {
-				$baseKey = "{$prefix}_namespace";
+
+		$deleteWheres = []; // list of WHERE clause arrays for each DB delete() call
+		if ( $table === 'pagelinks' || $table === 'templatelinks' || $table === 'iwlinks' ) {
+			$baseKey =  ( $table === 'iwlinks' ) ? 'iwl_prefix' : "{$prefix}_namespace";
+
+			$curBatchSize = 0;
+			$curDeletionBatch = [];
+			$deletionBatches = [];
+			foreach ( $deletions as $ns => $dbKeys ) {
+				foreach ( $dbKeys as $dbKey => $unused ) {
+					$curDeletionBatch[$ns][$dbKey] = 1;
+					if ( ++$curBatchSize >= $bSize ) {
+						$deletionBatches[] = $curDeletionBatch;
+						$curDeletionBatch = [];
+						$curBatchSize = 0;
+					}
+				}
 			}
-			$clause = $this->mDb->makeWhereFrom2d( $deletions, $baseKey, "{$prefix}_title" );
-			if ( $clause ) {
-				$where[] = $clause;
-			} else {
-				$where = false;
+			if ( $curDeletionBatch ) {
+				$deletionBatches[] = $curDeletionBatch;
+			}
+
+			foreach ( $deletionBatches as $deletionBatch ) {
+				$deleteWheres[] = [
+					$fromField => $this->mId,
+					$this->mDb->makeWhereFrom2d( $deletionBatch, $baseKey, "{$prefix}_title" )
+				];
 			}
 		} else {
-			if ( $table == 'langlinks' ) {
+			if ( $table === 'langlinks' ) {
 				$toField = 'll_lang';
-			} elseif ( $table == 'page_props' ) {
+			} elseif ( $table === 'page_props' ) {
 				$toField = 'pp_propname';
 			} else {
 				$toField = $prefix . '_to';
 			}
-			if ( count( $deletions ) ) {
-				$where[$toField] = array_keys( $deletions );
-			} else {
-				$where = false;
+
+			$deletionBatches = array_chunk( array_keys( $deletions ), $bSize );
+			foreach ( $deletionBatches as $deletionBatch ) {
+				$deleteWheres[] = [ $fromField => $this->mId, $toField => $deletionBatch ];
 			}
 		}
-		if ( $where ) {
-			$this->mDb->delete( $table, $where, __METHOD__ );
+
+		foreach ( $deleteWheres as $deleteWhere ) {
+			$this->mDb->delete( $table, $deleteWhere, __METHOD__ );
+			$this->mDb->commit( __METHOD__, 'flush' );
+			wfGetLBFactory()->waitForReplication( [ 'wiki' => $this->mDb->getWikiID() ] );
 		}
+
+		$insertBatches = array_chunk( $insertions, $bSize );
+		foreach ( $insertBatches as $insertBatch ) {
+			$this->mDb->insert( $table, $insertBatch, __METHOD__, 'IGNORE' );
+			$this->mDb->commit( __METHOD__, 'flush' );
+			wfGetLBFactory()->waitForReplication( [ 'wiki' => $this->mDb->getWikiID() ] );
+		}
+
 		if ( count( $insertions ) ) {
-			$this->mDb->insert( $table, $insertions, __METHOD__, 'IGNORE' );
 			Hooks::run( 'LinksUpdateAfterInsert', [ $this, $table, $insertions ] );
 		}
 	}
@@ -875,6 +933,14 @@ class LinksUpdate extends SqlDataUpdate implements EnqueueableDataUpdate {
 		$this->mRevision = $revision;
 	}
 
+	/**
+	 * @since 1.28
+	 * @return null|Revision
+	 */
+	public function getRevision() {
+		return $this->mRevision;
+	}
+
 	/**
 	 * Set the User who triggered this LinksUpdate
 	 *