From: Tom Lane <tgl@sss.pgh.pa.us>
To: Ron Johnson <ronljohnsonjr@gmail.com>
cc: Pgsql-admin <pgsql-admin@lists.postgresql.org>
Subject: Re: Does export operation cancel SQLs?
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Comments: In-reply-to Ron Johnson <ronljohnsonjr@gmail.com>
	message dated "Wed, 19 Feb 2025 10:42:54 -0500"
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Date: Wed, 19 Feb 2025 11:03:41 -0500
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Ron Johnson <ronljohnsonjr@gmail.com> writes:
> On Wed, Feb 19, 2025 at 10:00 AM Laurenz Albe <laurenz.albe@cybertec.at>
> wrote:
>> No, that message is from a cancel request, like when you interrupt your
>> currently running query with Ctrl+C in "psql" or invoke
>> pg_cancel_backend().
>> PostgreSQL doesn't do that by itself.

> The Linux oom killer?  I don't remember the exact error message that PG
> gives to the user, but ISTR that it's "user request”.

No, the OOM killer does "kill -9", which stops the PG process in
its tracks.  So no message at all will be issued.  You'll get
some kind of "connection lost" message from the connected client,
but for sure that is not going to claim it was a "user request".

I do seem to recall that there are some edge cases where we can't
really tell the source of a SIGINT signal, but there's no reason
to think that any of those cases are in play here.  The OP should
be looking first at the other moving parts in his installation
to see what might be issuing a query cancel.

			regards, tom lane