From: Aaron Schulz <aschulz@wikimedia.org>
Date: Fri, 23 Aug 2019 00:58:47 +0000 (-0700)
Subject: rdbms: remove reference to READ_LATEST in ChronologyProtector::shutdown()
X-Git-Tag: 1.34.0-rc.0~617^2
X-Git-Url: http://git.cyclocoop.org/%7B%24www_url%7Dadmin/compta/pie.php?a=commitdiff_plain;h=dcc7717fec6cbaf96445ea6bc2a24c206f5b8abb;p=lhc%2Fweb%2Fwiklou.git

rdbms: remove reference to READ_LATEST in ChronologyProtector::shutdown()

Change-Id: I34b2fa940475d5e5e81130221f61d782818a6d17
---

diff --git a/includes/libs/rdbms/ChronologyProtector.php b/includes/libs/rdbms/ChronologyProtector.php
index 8615cfc630..e1398b815b 100644
--- a/includes/libs/rdbms/ChronologyProtector.php
+++ b/includes/libs/rdbms/ChronologyProtector.php
@@ -224,10 +224,9 @@ class ChronologyProtector implements LoggerAwareInterface {
 			implode( ', ', array_keys( $this->shutdownPositions ) ) . "\n"
 		);
 
-		// CP-protected writes should overwhelmingly go to the master datacenter, so use a
-		// DC-local lock to merge the values. Use a DC-local get() and a synchronous all-DC
-		// set(). This makes it possible for the BagOStuff class to write in parallel to all
-		// DCs with one RTT. The use of WRITE_SYNC avoids needing READ_LATEST for the get().
+		// CP-protected writes should overwhelmingly go to the master datacenter, so merge the
+		// positions with a DC-local lock, a DC-local get(), and an all-DC set() with WRITE_SYNC.
+		// If set() returns success, then any get() should be able to see the new positions.
 		if ( $store->lock( $this->key, 3 ) ) {
 			if ( $workCallback ) {
 				// Let the store run the work before blocking on a replication sync barrier.