Feedback-ID: i0fe9450f:Fastmail
Date: Wed, 25 Mar 2026 11:19:15 +0900
From: Michael Paquier <michael@paquier.xyz>
To: Srinath Reddy Sadipiralla <srinath2133@gmail.com>
Cc: Antonin Houska <ah@cybertec.at>, pgsql-hackers@lists.postgresql.org
Subject: Re: Teach isolation tester about injection points in background
 workers
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On Tue, Mar 24, 2026 at 04:25:47PM +0530, Srinath Reddy Sadipiralla wrote:
> +1. I was thinking can we move the logic of checking if bg workers are the
> reason of blocking the main backend
> inside pg_isolation_test_session_is_blocked
> to make it cleaner, and regarding "XXX Should we use a separate query for
> that?"
> i am confused here IIUC if we keep it as 1 query using UNION every time its
> for sure
> that both the queries will run, which can increase more execution time but
> less libpq/socket
> calls, but if we send as 2 queries if 1st query doesn't returns true we
> have to go and
> check the other query, so here if 2 queries ran then execution +
> libpq/socket calls overhead,
> so i am slightly inclined towards separating the queries , so that if 1st
> gets satisfied then
> we don't touch the 2nd query at all, please correct me if i am wrong here :)

Is there a benefit in this change outside the hypothetical REPACK
CONCURRENTLY?  Using separating queries may make more sense on
readability ground, at least.
--
Michael

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