Feedback-ID: i0fe9450f:Fastmail
Date: Wed, 25 Mar 2026 14:11:00 +0900
From: Michael Paquier <michael@paquier.xyz>
To: Roman Khapov <rkhapov@yandex-team.ru>
Cc: Andrey Borodin <x4mmm@yandex-team.ru>,
	"pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Subject: Re: [PATCH v2] Re: Cancel problems of query to pg_stat_statements
Message-ID: <acNuZJJORIgbZ03a@paquier.xyz>
References: <31431745515032@mail.yandex-team.ru>
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On Mon, May 12, 2025 at 03:48:29PM +0500, Roman Khapov wrote:
> Its true that qtext_load_file() can be called with acquired lock in
> pg_stat_statements_internal()...
> So I perform INTERRUPTS_PENDING_CONDITION in v2 patch and call
> CHECK_FOR_INTERRUPTS later, after cycle ended and lock released.

This patch is only a workaround for a larger problem: the PGSS text
file does not and will never scale once it reaches a large size and
once we have a high turnover rate of the PGSS entries due to different
query IDs.

FWIW, Sami Imseih has mentioned to me a few days ago that the state of
the pgstats API (that can be used for custom stats kinds as well) was
basically in a shape good enough to move PGSS to pgstats as a custom
kind, and we should be able to move the query text file to be entirely
in-memory.  This proposal will hopefully materialize at the beginning
of the v20 cycle.
--
Michael

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