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Date: Wed, 01 Oct 2025 08:57:38 -0300
Message-Id: <DD6YU9L1S3TS.2HLPSHSMNYRWV@gmail.com>
From: "Matheus Alcantara" <matheusssilv97@gmail.com>
To: "Arseniy Mukhin" <arseniy.mukhin.dev@gmail.com>, "Matheus Alcantara"
 <matheusssilv97@gmail.com>
Cc: "Masahiko Sawada" <sawada.mshk@gmail.com>, "Rishu Bagga"
 <rishu.postgres@gmail.com>, "Yura Sokolov" <y.sokolov@postgrespro.ru>,
 "Daniil Davydov" <3danissimo@gmail.com>, =?utf-8?q?=C3=81lvaro_Herrera?=
 <alvherre@kurilemu.de>, "Alexandra Wang" <alexandra.wang.oss@gmail.com>,
 "PostgreSQL Hackers" <pgsql-hackers@postgresql.org>, "Tom Lane"
 <tgl@sss.pgh.pa.us>, "Joel Jacobson" <joel@compiler.org>
Subject: Re: LISTEN/NOTIFY bug: VACUUM sets frozenxid past a xid in async
 queue
References: 
 <CAK98qZ3wZLE-RZJN_Y+TFjiTRPPFPBwNBpBi5K5CU8hUHkzDpw@mail.gmail.com>
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On Sun Sep 28, 2025 at 10:17 AM -03, Arseniy Mukhin wrote:
>> I agree it would be great to have more tests for such cases. As for
>> the 'committed field' patch, I think we can add a TAP test that shows
>> that listeners postpone processing of notifications until
>> notifications were marked as 'committed=3Dfalse' in case of aborted
>> transactions. I tried to write one, but have not succeeded yet. Hope
>> to finish it soon.
>
> I finally managed to write a TAP test for it, so there is a new
> version with the tap test.
>
> I also realized that we can increase test coverage in
> 002_aborted_tx_notifies.pl if notifications of the aborted transaction
> span several pages. This way we can better test
> asyncQueueRollbackNotifications(). So I changed
> 002_aborted_tx_notifies.pl TAP test a bit.
>
> And there is a small indentation change in lmgr.h that should fix this
> git am warning.
>
Thanks for the patches.

I've created a CF entry so we can get more reviews and comments:
https://commitfest.postgresql.org/patch/6095/

Let's see what other think about the approach being used to fix this
issue.

--
Matheus Alcantara