Date: Thu, 23 Oct 2025 13:47:51 -0500
From: Nathan Bossart <nathandbossart@gmail.com>
To: Sami Imseih <samimseih@gmail.com>
Cc: David Rowley <dgrowleyml@gmail.com>,
	Robert Haas <robertmhaas@gmail.com>,
	Jeremy Schneider <schneider@ardentperf.com>,
	pgsql-hackers@postgresql.org
Subject: Re: another autovacuum scheduling thread
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On Thu, Oct 23, 2025 at 01:22:24PM -0500, Sami Imseih wrote:
> I was looking at v3, and I understand the formula will be updated in the
> next version. However, do you think we should benchmark the approach
> of using an intermediary list to store the eligible tables and sorting
> that list,
> which may cause larger performance overhead for databases with hundreds
> of tables that may all be eligible for autovacuum. I do think such cases
> out there are common, particularly in multi-tenant type databases, where
> each tenant could be one or more tables.

We already have an intermediary list of table OIDs, so the additional
overhead is ultimately just the score calculation and the sort operation.
I'd be quite surprised if that added up to anything remotely worrisome,
even for thousands of eligible tables.

-- 
nathan