From: Aaron Schulz <aschulz@wikimedia.org>
Date: Tue, 17 May 2016 11:19:29 +0000 (-0700)
Subject: Limit DELETE in purgeExpiredRestrictions() and use primary key
X-Git-Tag: 1.31.0-rc.0~6896^2
X-Git-Url: https://git.cyclocoop.org/%7B%7B%20url_for%28?a=commitdiff_plain;h=d58f0155df6b2cec1d8d691d877f19c0dc0a873d;p=lhc%2Fweb%2Fwiklou.git

Limit DELETE in purgeExpiredRestrictions() and use primary key

This should help reduce contention in some cases.
If too many rows are expired, subsequent updates will
clear them out.

Bug: T135470
Change-Id: Iada496d0db9b00e77037320d7c65124a8c8f68c0
---

diff --git a/includes/Title.php b/includes/Title.php
index 25fbce3f57..3a5b62b333 100644
--- a/includes/Title.php
+++ b/includes/Title.php
@@ -2971,6 +2971,8 @@ class Title implements LinkTarget {
 
 	/**
 	 * Purge expired restrictions from the page_restrictions table
+	 *
+	 * This will purge no more than $wgUpdateRowsPerQuery page_restrictions rows
 	 */
 	static function purgeExpiredRestrictions() {
 		if ( wfReadOnly() ) {
@@ -2981,11 +2983,24 @@ class Title implements LinkTarget {
 			wfGetDB( DB_MASTER ),
 			__METHOD__,
 			function ( IDatabase $dbw, $fname ) {
-				$dbw->delete(
+				$config = MediaWikiServices::getInstance()->getMainConfig();
+				$ids = $dbw->selectFieldValues(
 					'page_restrictions',
+					'pr_id',
 					[ 'pr_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ],
-					$fname
+					$fname,
+					[ 'LIMIT' => $config->get( 'UpdateRowsPerQuery' ) ] // T135470
 				);
+				if ( $ids ) {
+					$dbw->delete( 'page_restrictions', [ 'pr_id' => $ids ], $fname );
+				}
+			}
+		) );
+
+		DeferredUpdates::addUpdate( new AtomicSectionUpdate(
+			wfGetDB( DB_MASTER ),
+			__METHOD__,
+			function ( IDatabase $dbw, $fname ) {
 				$dbw->delete(
 					'protected_titles',
 					[ 'pt_expiry < ' . $dbw->addQuotes( $dbw->timestamp() ) ],