Date: Wed, 19 Feb 2025 15:59:54 -0600
From: Nathan Bossart <nathandbossart@gmail.com>
To: Melanie Plageman <melanieplageman@gmail.com>
Cc: Pg Hackers <pgsql-hackers@postgresql.org>,
	Robert Haas <robertmhaas@gmail.com>,
	Andres Freund <andres@anarazel.de>, Peter Geoghegan <pg@bowt.ie>,
	David Rowley <dgrowley@gmail.com>
Subject: Re: Trigger more frequent autovacuums of heavy insert tables
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On Wed, Feb 19, 2025 at 04:36:05PM -0500, Melanie Plageman wrote:
> This makes me think I should also not cap relallfrozen when using it
> in relation_needs_vacanalyze(). There I cap it to relallvisible and
> relallvisible is capped to relpages. One of the ideas behind letting
> people modify these stats in pg_class is that they can change a single
> field to see what the effect on their system is, right?

Right.  Capping these values to reflect reality seems like it could make
that more difficult.

>> Should we allow manipulating relallfrozen like we do relallvisible?  My
>> assumption is that would even be required for the ongoing statistics
>> import/export work.
> 
> Why would it be required for the statistics import/export work?

It's probably not strictly required, but my naive expectation would be that
we'd handle relallfrozen just like relallvisible, which appears to be
dumped in the latest stats import/export patch.  Is there any reason we
shouldn't do the same for relallfrozen?

-- 
nathan