Feedback-ID: i0fe9450f:Fastmail
Date: Mon, 2 Feb 2026 16:31:48 +0900
From: Michael Paquier <michael@paquier.xyz>
To: Sami Imseih <samimseih@gmail.com>
Cc: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>,
	Fujii Masao <masao.fujii@gmail.com>,
	pgsql-hackers@lists.postgresql.org,
	Zsolt Parragi <zsolt.parragi@percona.com>
Subject: Re: Flush some statistics within running transactions
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On Sat, Jan 31, 2026 at 11:16:03AM -0600, Sami Imseih wrote:
> Also, the anytime flush callback does not need to check if there are
> any variable-numbered stats to flush. This will not be needed as
> it is in v4-0004
>=20
> ```
> + /*
> + * Check if there are any non-transactional stats to flush. Avoid
> + * unnecessarily locking the entry if nothing accumulated.
> + */
> + if (!(lstats->counts.numscans > 0 ||
> +  lstats->counts.tuples_returned > 0 ||
> +  lstats->counts.tuples_fetched > 0 ||
> +  lstats->counts.blocks_fetched > 0 ||
> +  lstats->counts.blocks_hit > 0))
> + return true;
> ```

I think that this kind of check may finish by being expensive.
Reducing the number of fields to check for a non-flushing state, if
required, would be preferrable.
--
Michael

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