Date: Fri, 31 Oct 2025 15:12:47 -0500
From: Nathan Bossart <nathandbossart@gmail.com>
To: Sami Imseih <samimseih@gmail.com>
Cc: Robert Haas <robertmhaas@gmail.com>,
	David Rowley <dgrowleyml@gmail.com>,
	Jeremy Schneider <schneider@ardentperf.com>,
	pgsql-hackers@postgresql.org
Subject: Re: another autovacuum scheduling thread
Message-ID: <aQUYP1WjrEP3buQz@nathan>
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On Thu, Oct 30, 2025 at 07:38:15PM -0500, Sami Imseih wrote:
> Here is my attempt to test the behavior with the new prioritization.

Thanks.

> The results above show what I expected: the batch tables receive higher
> priority, as seen from the averages of autovacuum and autoanalyze runs.
> This behavior is expected, but it may catch some users by surprise after
> an upgrade, since certain tables will now receive more attention than
> others. Longer tests might also show more bloat accumulating on heavily
> updated tables. In such cases, a user may need to adjust autovacuum
> settings on a per-table basis to restore the previous behavior.

Interesting.  From these results, it almost sounds as if we're further
amplifying the intended effect of commit 06eae9e.  That could be a good
thing.  Something else I'm curious about is datfrozenxid, i.e., whether
prioritization keeps the database (M)XID ages lower.

-- 
nathan