From: Aaron Schulz <aschulz@wikimedia.org>
Date: Wed, 18 Jan 2017 22:39:23 +0000 (-0800)
Subject: Avoid master queries when old filter checks are viewed
X-Git-Tag: 1.31.0-rc.0~4221^2
X-Git-Url: http://git.cyclocoop.org///%22%40url%40//%22?a=commitdiff_plain;h=40e6862ae6f708d603df8b4d7ce4683991918ff2;p=lhc%2Fweb%2Fwiklou.git

Avoid master queries when old filter checks are viewed

Bug: T154554
Change-Id: I5ca7f0ea22c337c38083532291400df8c7db1e11
---

diff --git a/includes/page/WikiPage.php b/includes/page/WikiPage.php
index 920ba87806..d582d51bf6 100644
--- a/includes/page/WikiPage.php
+++ b/includes/page/WikiPage.php
@@ -2150,8 +2150,12 @@ class WikiPage implements Page, IDBAccessObject {
 				);
 			} else {
 				// Try to avoid a second parse if {{REVISIONID}} is used
-				$edit->popts->setSpeculativeRevIdCallback( function () {
-					return 1 + (int)wfGetDB( DB_MASTER )->selectField(
+				$dbIndex = ( $this->mDataLoadedFrom & self::READ_LATEST ) === self::READ_LATEST
+					? DB_MASTER // use the best possible guess
+					: DB_REPLICA; // T154554
+
+				$edit->popts->setSpeculativeRevIdCallback( function () use ( $dbIndex ) {
+					return 1 + (int)wfGetDB( $dbIndex )->selectField(
 						'revision',
 						'MAX(rev_id)',
 						[],