Introduce a WaitEventSet for the stats collector.
This avoids avoids some epoll/kqueue system calls for every wait.
Discussion:
@@ -4458,6 +4458,8 @@ PgstatCollectorMain(int argc, char *argv[])
int len;
PgStat_Msg msg;
int wr;
+ WaitEvent event;
+ WaitEventSet *wes;
/*
* Ignore all signals usually bound to some action in the postmaster,
@@ -4485,6 +4487,12 @@ PgstatCollectorMain(int argc, char *argv[])
pgStatRunningInCollector = true;
pgStatDBHash = pgstat_read_statsfiles(InvalidOid, true, true);
+ /* Prepare to wait for our latch or data in our socket. */
+ wes = CreateWaitEventSet(CurrentMemoryContext, 3);
+ AddWaitEventToSet(wes, WL_LATCH_SET, PGINVALID_SOCKET, MyLatch, NULL);
+ AddWaitEventToSet(wes, WL_POSTMASTER_DEATH, PGINVALID_SOCKET, NULL, NULL);
+ AddWaitEventToSet(wes, WL_SOCKET_READABLE, pgStatSock, NULL, NULL);
+
/*
* Loop to process messages until we get SIGQUIT or detect ungraceful
* death of our parent postmaster.
@@ -4672,10 +4680,7 @@ PgstatCollectorMain(int argc, char *argv[])
/* Sleep until there's something to do */
#ifndef WIN32
- wr = WaitLatchOrSocket(MyLatch,
- WL_LATCH_SET | WL_POSTMASTER_DEATH | WL_SOCKET_READABLE,
- pgStatSock, -1L,
- WAIT_EVENT_PGSTAT_MAIN);
+ wr = WaitEventSetWait(wes, -1L, &event, 1, WAIT_EVENT_PGSTAT_MAIN);
#else
/*
@@ -4688,10 +4693,7 @@ PgstatCollectorMain(int argc, char *argv[])
* to not provoke "using stale statistics" complaints from
* backend_read_statsfile.
*/
- wr = WaitLatchOrSocket(MyLatch,
- WL_LATCH_SET | WL_POSTMASTER_DEATH | WL_SOCKET_READABLE | WL_TIMEOUT,
- pgStatSock,
- 2 * 1000L /* msec */ ,
+ wr = WaitEventSetWait(wes, 2 * 1000L /* msec */ , &event, 1,
WAIT_EVENT_PGSTAT_MAIN);
#endif
@@ -4699,7 +4701,7 @@ PgstatCollectorMain(int argc, char *argv[])
* Emergency bailout if postmaster has died. This is to avoid the
* necessity for manual cleanup of all postmaster children.
*/
- if (wr & WL_POSTMASTER_DEATH)
+ if (wr == 1 && event.events == WL_POSTMASTER_DEATH)
break;
} /* end of outer loop */
@@ -4708,6 +4710,8 @@ PgstatCollectorMain(int argc, char *argv[])
*/
pgstat_write_statsfiles(true, true);
+ FreeWaitEventSet(wes);
+
exit(0);
}
