postgres.git / summary / log / commit / refs

commit    6ea812f4dc634af01feb06fc3da45d53f5a1ec83
Author:   Michael Paquier <michael@paquier.xyz>
Date:     Mon May 26 08:28:40 2025 +0000

    Fix race condition in subscription TAP test 021_twophase
    
    The test did not wait for all the subscriptions to have caught up when
    dropping the subscription "tab_copy".  In a slow environment, it could
    be possible for the replay of the COMMIT PREPARED transaction "mygid"
    to not be confirmed yet, causing one prepared transaction to be left
    around before moving to the next steps of the test.
    
    One failure noticed is a transaction found in pg_prepared_xacts for the
    cases where copy_data = false and two_phase = true, but there should be
    none after dropping the subscription.
    
    As an extra safety measure, a check is added before dropping the
    subscription, scanning pg_prepared_xacts to make sure that no prepared
    transactions are left once both subscriptions have caught up.
    
    Issue introduced by a8fd13cab0ba, fixing a problem similar to
    eaf5321c3524.
    
    Per buildfarm member kestrel.
    
    Author: Vignesh C <vignesh21@gmail.com>
    Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
    Discussion: https://postgr.es/m/CALDaNm329QaZ+bwU--bW6GjbNSZ8-38cDE8QWofafub7NV67oA@mail.gmail.com
    Backpatch-through: 15


 src/test/subscription/t/021_twophase.pl | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/test/subscription/t/021_twophase.pl b/src/test/subscription/t/021_twophase.pl
index e635be74c63..94a6d53794e 100644
--- a/src/test/subscription/t/021_twophase.pl
+++ b/src/test/subscription/t/021_twophase.pl
@@ -373,7 +373,14 @@ $result =
   $node_publisher->safe_psql('postgres', "SELECT count(*) FROM tab_copy;");
 is($result, qq(6), 'publisher inserted data');
 
+# Wait for both subscribers to catchup
 $node_publisher->wait_for_catchup($appname_copy);
+$node_publisher->wait_for_catchup($appname);
+
+# Make sure there are no prepared transactions on the subscriber
+$result = $node_subscriber->safe_psql('postgres',
+	"SELECT count(*) FROM pg_prepared_xacts;");
+is($result, qq(0), 'should be no prepared transactions on subscriber');
 
 $result =
   $node_subscriber->safe_psql('postgres', "SELECT count(*) FROM tab_copy;");


[parent: 90558dbf5483]