From e2088f1170b2867ca3ababe205137cc6ad010068 Mon Sep 17 00:00:00 2001
From: Aaron Schulz <aschulz@wikimedia.org>
Date: Sat, 27 Oct 2018 07:34:52 -0700
Subject: [PATCH] Make UserEditCountUpdate faster by using auto-commit mode

Bug: T202715
Change-Id: I92c08694cb5e1c367809439cff42e33a56ff9878
---
 includes/deferred/UserEditCountUpdate.php | 78 +++++++++++------------
 includes/user/User.php                    |  9 +--
 2 files changed, 44 insertions(+), 43 deletions(-)

diff --git a/includes/deferred/UserEditCountUpdate.php b/includes/deferred/UserEditCountUpdate.php
index 2a1205c675..5194e4f1cc 100644
--- a/includes/deferred/UserEditCountUpdate.php
+++ b/includes/deferred/UserEditCountUpdate.php
@@ -66,48 +66,48 @@ class UserEditCountUpdate implements DeferrableUpdate, MergeableUpdate {
 	 * Purges the list of URLs passed to the constructor.
 	 */
 	public function doUpdate() {
-		foreach ( $this->infoByUser as $userId => $info ) {
-			$lb = MediaWikiServices::getInstance()->getDBLoadBalancer();
-			$dbw = $lb->getConnection( DB_MASTER );
+		$lb = MediaWikiServices::getInstance()->getDBLoadBalancer();
+		$dbw = $lb->getConnection( DB_MASTER );
 
-			$dbw->startAtomic( __METHOD__ ); // define minimum row lock duration
-			$dbw->update(
-				'user',
-				[ 'user_editcount=user_editcount+' . (int)$info['increment'] ],
-				[ 'user_id' => $userId, 'user_editcount IS NOT NULL' ],
-				__METHOD__
-			);
-			/** @var User[] $affectedInstances */
-			$affectedInstances = $info['instances'];
-			// Lazy initialization check...
-			if ( $dbw->affectedRows() == 0 ) {
-				// No rows will be "affected" if user_editcount is NULL.
-				// Get the generic "replica" connection to see if it actually uses the master.
-				$dbr = $lb->getConnection( DB_REPLICA );
-				if ( $dbr !== $dbw ) {
-					// This method runs after the new revisions were committed.
-					// Wait for the replica to catch up so they will all be counted.
-					$dbr->flushSnapshot( __METHOD__ );
-					$lb->safeWaitForMasterPos( $dbr );
+		( new AutoCommitUpdate( $dbw, __METHOD__, function () use ( $lb, $dbw ) {
+			foreach ( $this->infoByUser as $userId => $info ) {
+				$dbw->update(
+					'user',
+					[ 'user_editcount=user_editcount+' . (int)$info['increment'] ],
+					[ 'user_id' => $userId, 'user_editcount IS NOT NULL' ],
+					__METHOD__
+				);
+				/** @var User[] $affectedInstances */
+				$affectedInstances = $info['instances'];
+				// Lazy initialization check...
+				if ( $dbw->affectedRows() == 0 ) {
+					// No rows will be "affected" if user_editcount is NULL.
+					// Check if the generic "replica" connection is not the master.
+					$dbr = $lb->getConnection( DB_REPLICA );
+					if ( $dbr !== $dbw ) {
+						// This method runs after the new revisions were committed.
+						// Wait for the replica to catch up so they will all be counted.
+						$dbr->flushSnapshot( __METHOD__ );
+						$lb->safeWaitForMasterPos( $dbr );
+					}
+					$affectedInstances[0]->initEditCountInternal();
 				}
-				$affectedInstances[0]->initEditCountInternal();
-			}
-			$newCount = (int)$dbw->selectField(
-				'user',
-				[ 'user_editcount' ],
-				[ 'user_id' => $userId ],
-				__METHOD__
-			);
-			$dbw->endAtomic( __METHOD__ );
+				$newCount = (int)$dbw->selectField(
+					'user',
+					[ 'user_editcount' ],
+					[ 'user_id' => $userId ],
+					__METHOD__
+				);
 
-			// Update the edit count in the instance caches. This is mostly useful
-			// for maintenance scripts, where deferred updates might run immediately
-			// and user instances might be reused for a long time.
-			foreach ( $affectedInstances as $affectedInstance ) {
-				$affectedInstance->setEditCountInternal( $newCount );
+				// Update the edit count in the instance caches. This is mostly useful
+				// for maintenance scripts, where deferred updates might run immediately
+				// and user instances might be reused for a long time.
+				foreach ( $affectedInstances as $affectedInstance ) {
+					$affectedInstance->setEditCountInternal( $newCount );
+				}
+				// Clear the edit count in user cache too
+				$affectedInstances[0]->invalidateCache();
 			}
-			// Clear the edit count in user cache too
-			$affectedInstances[0]->invalidateCache();
-		}
+		} ) )->doUpdate();
 	}
 }
diff --git a/includes/user/User.php b/includes/user/User.php
index 9cd3ea1611..43be06e717 100644
--- a/includes/user/User.php
+++ b/includes/user/User.php
@@ -5350,10 +5350,9 @@ class User implements IDBAccessObject, UserIdentity {
 	 *
 	 * This method should not be called outside User/UserEditCountUpdate
 	 *
-	 * @param int $add Edits to add to the count from the revision table
 	 * @return int Number of edits
 	 */
-	public function initEditCountInternal( $add = 0 ) {
+	public function initEditCountInternal() {
 		// Pull from a replica DB to be less cruel to servers
 		// Accuracy isn't the point anyway here
 		$dbr = wfGetDB( DB_REPLICA );
@@ -5366,13 +5365,15 @@ class User implements IDBAccessObject, UserIdentity {
 			[],
 			$actorWhere['joins']
 		);
-		$count = $count + $add;
 
 		$dbw = wfGetDB( DB_MASTER );
 		$dbw->update(
 			'user',
 			[ 'user_editcount' => $count ],
-			[ 'user_id' => $this->getId() ],
+			[
+				'user_id' => $this->getId(),
+				'user_editcount IS NULL OR user_editcount < ' . (int)$count
+			],
 			__METHOD__
 		);
 
-- 
2.20.1