Feedback-ID: i0fe9450f:Fastmail
Date: Fri, 24 Oct 2025 08:33:17 +0900
From: Michael Paquier <michael@paquier.xyz>
To: Sami Imseih <samimseih@gmail.com>
Cc: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: [Proposal] Adding callback support for custom statistics kinds
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On Thu, Oct 23, 2025 at 04:35:58PM -0500, Sami Imseih wrote:
> Perhaps if someone wants to have separate files for each different
> types of data,
> we should be able to support multiple files. I think we can add an
> option for the
> number of files and they can then be named "pgstat.<kind>.1.stat",
> pgstat.<kind>.2.stat",
> etc. I rather avoid having the extension provide a set of files names.
> So as arguments to the callback, besides the main file pointer ( as
> you mention below),
> we also provide the list of custom file pointers.
>=20
> what do you think?

My worry here is the lack of flexibility regarding stats that could be
split depending on the objects whose data needs to be flushed.  For
example, stats split across multiple databases (like our good-old
pre-v14 pgstats, but on a per-kind basis).  So I don't think that we
can really assume that the list of file names should be fixed when we
begin the read/write process of the main pgstats file.
--
Michael

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