From e101dfac3a53c20bfbf1ca85d30a368c2954facf Mon Sep 17 00:00:00 2001 From: Andres Freund Date: Sat, 8 Apr 2023 00:24:24 -0700 Subject: For cascading replication, wake physical and logical walsenders separately Physical walsenders can't send data until it's been flushed; logical walsenders can't decode and send data until it's been applied. On the standby, the WAL is flushed first, which will only wake up physical walsenders; and then applied, which will only wake up logical walsenders. Previously, all walsenders were awakened when the WAL was flushed. That was fine for logical walsenders on the primary; but on the standby the flushed WAL would have been not applied yet, so logical walsenders were awakened too early. Per idea from Jeff Davis and Amit Kapila. Author: "Drouvot, Bertrand" Reviewed-By: Jeff Davis Reviewed-By: Robert Haas Reviewed-by: Amit Kapila Reviewed-by: Masahiko Sawada Discussion: https://postgr.es/m/CAA4eK1+zO5LUeisabX10c81LU-fWMKO4M9Wyg1cdkbW7Hqh6vQ@mail.gmail.com --- src/backend/access/transam/xlog.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'src/backend/access/transam/xlog.c') diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c index 13f83dd57d6..1b7c2f23a41 100644 --- a/src/backend/access/transam/xlog.c +++ b/src/backend/access/transam/xlog.c @@ -2645,7 +2645,7 @@ XLogFlush(XLogRecPtr record) END_CRIT_SECTION(); /* wake up walsenders now that we've released heavily contended locks */ - WalSndWakeupProcessRequests(); + WalSndWakeupProcessRequests(true, !RecoveryInProgress()); /* * If we still haven't flushed to the request point then we have a @@ -2816,7 +2816,7 @@ XLogBackgroundFlush(void) END_CRIT_SECTION(); /* wake up walsenders now that we've released heavily contended locks */ - WalSndWakeupProcessRequests(); + WalSndWakeupProcessRequests(true, !RecoveryInProgress()); /* * Great, done. To take some work off the critical path, try to initialize @@ -5765,7 +5765,7 @@ StartupXLOG(void) * If there were cascading standby servers connected to us, nudge any wal * sender processes to notice that we've been promoted. */ - WalSndWakeup(); + WalSndWakeup(true, true); /* * If this was a promotion, request an (online) checkpoint now. This isn't -- cgit v1.2.3