From: Tom Lane <tgl@sss.pgh.pa.us>
To: Laurenz Albe <laurenz.albe@cybertec.at>
cc: Albrecht =?ISO-8859-1?Q?Dre=DF?= <albrecht.dress@netcologne.de>,
        pgsql-general@lists.postgresql.org
Subject: Re: ERROR: could not attach to dynamic shared area
In-reply-to: <ed04b49c6bac6abba9b3830e7b6d852f77040bec.camel@cybertec.at>
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 <ed04b49c6bac6abba9b3830e7b6d852f77040bec.camel@cybertec.at>
Comments: In-reply-to Laurenz Albe <laurenz.albe@cybertec.at>
	message dated "Wed, 24 Mar 2021 17:09:32 +0100"
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Date: Wed, 24 Mar 2021 12:12:48 -0400
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Laurenz Albe <laurenz.albe@cybertec.at> writes:
> On Wed, 2021-03-24 at 09:01 +0100, Albrecht Dre=C3=9F wrote:
>> in the logs of my database server, I found the following message:
>>> ERROR: could not attach to dynamic shared area
>>> LOG: background worker "parallel worker" (PID 51151) exited with exit =
code 1

> ... it could be a race condition: a parallel query finished rather fast,
> but one of the parallel workers took long to start up, so when it tries =
to
> attach to the dynamic shared memory segment used to exchange data betwee=
n the
> parallel processes, it realizes that everybody else has already left and
> destroyed the memory segment.

If the error only appeared in the log, and wasn't reported to the
client, then this theory seems pretty plausible.

			regards, tom lane