Add PostgreSQL::Test::Cluster::wait_for_event()

michaelpq · michaelpq · commit eca2c1ea85eb · 2024-03-04T10:27:50.000+09:00
Per a demand from the author and the reviewer of this commit, this adds to Cluster.pm a helper routine that can be used to monitor when a process reaches a wanted wait event. This can be used in combination with the module injection_points for the "wait" callback, though it is not limited to it as this monitors pg_stat_activity for a wait_event and a backend_type. Author: Bertrand Drouvot Reviewed-by: Andrey Borodin Discussion: https://postgr.es/m/ZeBB4RMPEZ06TcdY@ip-10-97-1-34.eu-west-3.compute.internal
diff --git a/src/test/perl/PostgreSQL/Test/Cluster.pm b/src/test/perl/PostgreSQL/Test/Cluster.pm
@@ -2742,6 +2742,29 @@ sub lsn
 
 =pod
 
+=item $node->wait_for_event(wait_event_name, backend_type)
+
+Poll pg_stat_activity until backend_type reaches wait_event_name.
+
+=cut
+
+sub wait_for_event
+{
+	my ($self, $backend_type, $wait_event_name) = @_;
+
+	$self->poll_query_until(
+		'postgres', qq[
+		SELECT count(*) > 0 FROM pg_stat_activity
+		WHERE backend_type = '$backend_type' AND wait_event = '$wait_event_name'
+	])
+	  or die
+	  qq(timed out when waiting for $backend_type to reach wait event '$wait_event_name');
+
+	return;
+}
+
+=pod
+
 =item $node->wait_for_catchup(standby_name, mode, target_lsn)
 
 Wait for the replication connection with application_name standby_name until
diff --git a/src/test/recovery/t/041_checkpoint_at_promote.pl b/src/test/recovery/t/041_checkpoint_at_promote.pl
@@ -78,13 +78,7 @@
 
 # Wait until the checkpointer is in the middle of the restart point
 # processing.
-ok( $node_standby->poll_query_until(
-		'postgres',
-		qq[SELECT count(*) FROM pg_stat_activity
-           WHERE backend_type = 'checkpointer' AND wait_event = 'create-restart-point' ;],
-		'1'),
-	'checkpointer is waiting in restart point'
-) or die "Timed out while waiting for checkpointer to run restart point";
+$node_standby->wait_for_event('checkpointer', 'create-restart-point');
 
 # Check the logs that the restart point has started on standby.  This is
 # optional, but let's be sure.
