Remove redundant WAIT FOR LSN caller-side pre-checks
All five wakeup call sites duplicate WaitLSNWakeup()'s internal
fast-path minWaitedLSN check and add an unnecessary NULL check
on waitLSNState.
Remove the inline pre-checks and call WaitLSNWakeup() directly.
The fast-path check inside WaitLSNWakeup() already returns early
when no waiter's target has been reached, so there is no
performance difference.
The waitLSNState NULL checks are also unnecessary: shared memory
is fully initialized before any backend or auxiliary process
starts, so waitLSNState is always non-NULL at these call sites.
Reported-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/jzq5shdewncpxc35r3s2mcfsmo4bjovkza5mnqf5bdfumhfi3g%40bglckf7dxmw5
Author: Xuneng Zhou <xunengzhou@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com>
Branch
------
master
Details
-------
https://git.postgresql.org/pg/commitdiff/df9f938ca2ec30e1018a76d80ccc77c7073d7acf
Modified Files
--------------
src/backend/access/transam/xlog.c | 16 ++++++----------
src/backend/access/transam/xlogrecovery.c | 11 ++++-------
src/backend/replication/walreceiver.c | 17 ++++++-----------
3 files changed, 16 insertions(+), 28 deletions(-)
