Feedback-ID: i0fe9450f:Fastmail
Date: Mon, 25 Nov 2024 16:18:54 +0900
From: Michael Paquier <michael@paquier.xyz>
To: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Cc: Nazir Bilal Yavuz <byavuz81@gmail.com>,
	Alvaro Herrera <alvherre@alvh.no-ip.org>,
	Kyotaro Horiguchi <horikyota.ntt@gmail.com>,
	pgsql-hackers@lists.postgresql.org
Subject: Re: per backend I/O statistics[
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On Mon, Nov 25, 2024 at 07:12:56AM +0000, Bertrand Drouvot wrote:
> Not sure here, could custom stats start incrementing before the database system
> is ready to accept connections?

In theory, that could be possible.  Like pg_stat_io currently, I am
ready to assume that it likely won't matter much.

> The only cons that I can see is that we will not be able to merge the flush cb
> but I don't think that's a blocker (the flush are done in shared memory so the
> impact on performance should not be that much of an issue).

The backend and I/O stats could begin diverging as a result of a new
implementation detail, and the performance of the flushes don't worry
me knowing at which frequency they happen on a live system.
--
Michael

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