Feedback-ID: i0fe9450f:Fastmail
Date: Mon, 6 Apr 2026 15:34:44 +0900
From: Michael Paquier <michael@paquier.xyz>
To: Andres Freund <andres@anarazel.de>
Cc: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>,
	Jeff Davis <pgsql@j-davis.com>,
	Greg Sabino Mullane <htamfids@gmail.com>,
	pgsql-hackers@lists.postgresql.org
Subject: Re: Adding locks statistics
Message-ID: <adNUBGqGK2YB1azG@paquier.xyz>
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On Mon, Apr 06, 2026 at 03:19:57PM +0900, Michael Paquier wrote:
> Now looking at it, and for the reason why 010 for concurrent indexes
> does not complain..

This one was a simple puzzle: there was a race condition between the
detach done by a local point and the wait/detach sequence.  As we want
a detach, dropping the local point is proving to work here.

I am going to do a few more runs to gain some more confidence.
Bertrand, could you confirm please?
--
Michael

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	filename=0001-Fix-detach-timing-problem-in-lock-stats-test.patch
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=46rom 684a26ad148a6d3d4261a633978702f76d7ee537 Mon Sep 17 00:00:00 2001
=46rom: Michael Paquier <michael@paquier.xyz>
Date: Mon, 6 Apr 2026 15:34:03 +0900
Subject: [PATCH] Fix detach timing problem in lock stats test

---
 src/test/modules/test_misc/t/011_lock_stats.pl | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/test/modules/test_misc/t/011_lock_stats.pl b/src/test/modu=
les/test_misc/t/011_lock_stats.pl
index 58a0046a52c3..908ade55a05f 100644
--- a/src/test/modules/test_misc/t/011_lock_stats.pl
+++ b/src/test/modules/test_misc/t/011_lock_stats.pl
@@ -31,9 +31,8 @@ sub setup_sessions
 	$s2 =3D $node->background_psql('postgres');
=20
 	# Setup injection points for the waiting session
-	$s2->query_safe(
-		q[
-			SELECT injection_points_set_local();
+	$s2->query_until(qr/attaching_injection_point/, q[
+			\echo attaching_injection_point
 			SELECT injection_points_attach('deadlock-timeout-fired', 'wait');
 		]);
 }
@@ -59,10 +58,11 @@ sub wait_and_detach
 	my ($node, $point_name) =3D @_;
=20
 	$node->wait_for_event('client backend', $point_name);
-	$node->safe_psql('postgres',
-		"SELECT injection_points_detach('$point_name');");
-	$node->safe_psql('postgres',
-		"SELECT injection_points_wakeup('$point_name');");
+	$node->safe_psql(
+		'postgres', qq[
+SELECT injection_points_detach('$point_name');
+SELECT injection_points_wakeup('$point_name');
+]);
 }
=20
 # Node initialization
--=20
2.53.0


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