From dcc7717fec6cbaf96445ea6bc2a24c206f5b8abb Mon Sep 17 00:00:00 2001 From: Aaron Schulz Date: Thu, 22 Aug 2019 17:58:47 -0700 Subject: [PATCH] rdbms: remove reference to READ_LATEST in ChronologyProtector::shutdown() Change-Id: I34b2fa940475d5e5e81130221f61d782818a6d17 --- includes/libs/rdbms/ChronologyProtector.php | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) 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. -- 2.20.1