Use a WaitLatch for vacuum/autovacuum sleeping

Instead of using pg_usleep() in vacuum_delay_point(), use a WaitLatch.
This has the advantage that we will realize if the postmaster has been
killed since the last time we decided to sleep while vacuuming.

Reviewed-by: Thomas Munro
Discussion: https://postgr.es/m/CAFh8B=kcdk8k-Y21RfXPu5dX=bgPqJ8TC3p_qxR_ygdBS=JN5w@mail.gmail.com

diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index c064352e237fb7468651f0dad5c58d8b5d017481..662aff04b45561ed8c6fdea92b8494a8b5ad5e7a 100644 (file)
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -2080,9 +2080,11 @@ vacuum_delay_point(void)
        if (msec > VacuumCostDelay * 4)
            msec = VacuumCostDelay * 4;
 
-       pgstat_report_wait_start(WAIT_EVENT_VACUUM_DELAY);
-       pg_usleep((long) (msec * 1000));
-       pgstat_report_wait_end();
+       (void) WaitLatch(MyLatch,
+                        WL_LATCH_SET | WL_TIMEOUT | WL_EXIT_ON_PM_DEATH,
+                        msec,
+                        WAIT_EVENT_VACUUM_DELAY);
+       ResetLatch(MyLatch);
 
        VacuumCostBalance = 0;