Message-ID: <512ef568-336e-4087-ba23-f22b006d329d@postgrespro.ru>
Date: Fri, 16 Feb 2024 21:40:03 +0700
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Subject: Re: BUG #18349: ERROR: invalid DSA memory alloc request size
 1811939328, CONTEXT: parallel worker
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To: alexey.ermakov@dataegret.com, pgsql-bugs@lists.postgresql.org,
 PG Bug reporting form <noreply@postgresql.org>
References: <18349-83d33dd3d0c855c3@postgresql.org>
From: Andrei Lepikhov <a.lepikhov@postgrespro.ru>
Organization: Postgres Professional
In-Reply-To: <18349-83d33dd3d0c855c3@postgresql.org>
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On 16/2/2024 20:18, PG Bug reporting form wrote:

> Interesting thing: after query fails it take some time (seconds) before psql
> gives control back.
> It turns out that postgresql written 1M+ (!) temporary files (most of them
> are empty) and cleaning up takes some time.
Interesting. It correlates with one performance issue I have been trying 
to catch already 3 months. Could you provide some reproduction of that 
behavior?
> With bigger work_mem it won't write so many files. Maybe memory issue
> somehow related with number of files.
> 
> In PostgreSQL 16.2 there were fix for similar bug: [1],[2]. Could it be that
> there is some issue with it ?
Looks like surely the same issue we fixed recently: Parallel Hash Join + 
DSM is a sign of that problem.

-- 
regards,
Andrei Lepikhov
Postgres Professional