Feedback-ID: i0fe9450f:Fastmail
Date: Mon, 9 Sep 2024 11:20:54 +0900
From: Michael Paquier <michael@paquier.xyz>
To: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Cc: Kyotaro Horiguchi <horikyota.ntt@gmail.com>,
	pgsql-hackers@lists.postgresql.org
Subject: Re: Add callbacks for fixed-numbered stats flush in pgstats
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On Wed, Sep 04, 2024 at 06:27:43AM +0000, Bertrand Drouvot wrote:
> Agree. The idea was to add an additional parameter (say "check_only") to the
> flush_fixed_cb. If this parameter is set to true then the flush_fixed_cb would
> do nothing (no flush at all) but return a boolean that would indicate if there
> is pending stats. In case it returns false, then we could avoid the clock check.

Hmm.  It's the same thing in terms of logic, but I am not really
convinced that it is a good idea to mix a code path for a sanity check
with a code path dealing with the action, particularly considering
that there is the nowait option to think about in the flush callback
which would require one to think about 4 possible states rather than
two possibilities.  So that's more error-prone for extension
developers, IMO.

At the end, I have used my original suggestions for the callbacks.  If
there are voices in favor of something different, we still have a good
chunk of the development and beta cycle for that.
--
Michael

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