Re: BUG #18909: Query creates millions of temporary files and stalls

KOPOSOV Sergey <sergey.koposov@ed.ac.uk>

From: Sergey Koposov <Sergey.Koposov@ed.ac.uk>

To: "tgl@sss.pgh.pa.us" <tgl@sss.pgh.pa.us>

Cc: "pgsql-bugs@lists.postgresql.org" <pgsql-bugs@lists.postgresql.org>

Date: 2025-05-02T22:44:19Z

Lists: pgsql-bugs

On Fri, 2025-05-02 at 18:12 -0400, Tom Lane wrote:
> PG Bug reporting form <noreply@postgresql.org> writes:
> > I have a query: ...
> > that I ran (from python client), and after it didn't finish in ~ an hour, i
> > started to investigate, finding that the pgsql_tmp folder had 15 million
> > temporary files from that query.
>
> Does it behave any better if you disable parallelism
> (set max_parallel_workers_per_gather = 0) ?

Yes, I've just tried and that also prevents the issue.

   S
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