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In-Reply-To: <abBEiOICOdbbhsEI@nathan>
From: Sami Imseih <samimseih@gmail.com>
Date: Tue, 10 Mar 2026 19:11:27 -0500
Message-ID: 
 <CAA5RZ0seLxDmH9UftUA3vS8DrW+7T9HV5XK8yAuQxA8BaRkg2g@mail.gmail.com>
Subject: Re: another autovacuum scheduling thread
To: Nathan Bossart <nathandbossart@gmail.com>
Cc: Robert Haas <robertmhaas@gmail.com>, David Rowley <dgrowleyml@gmail.com>,
	Robert Treat <rob@xzilla.net>, Jeremy Schneider <schneider@ardentperf.com>,
 pgsql-hackers@postgresql.org
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 <https://www.postgresql.org/message-id/CAA5RZ0seLxDmH9UftUA3vS8DrW%2B7T9HV5XK8yAuQxA8BaRkg2g%40mail.gmail.com>
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> Here's an updated patch with new GUCs that control how much each component
> contributes to the autovacuum score for a table.  They default to 1.0, but
> can be set anywhere from 0.0 to 1.0 (inclusive).  In theory, setting all of
> them to 0.0 should restore the original pg_class order prioritization that
> we have today.  I haven't added corresponding reloptions for these GUCs, as
> I'm not convinced we need them, but I can add them if folks think they
> would be useful.

Starting with GUCs is OK by me.

Just a few things:

1/
+        Oid            xid_age;
+        Oid            mxid_age;

Is using Oid here intentional? I'm curious why not use uint32 for clarity?

2/
The new GUC docs says  "...component of the score...", but without
introducing the concept of the prioritization score.
I think we should expand a bit more on this topic to help a user
understand and tune these more effectively. Attached is my
proposal for the docs. I tried to keep it informative without
being too verbose, and avoided making specific recommendations.

--
Sami Imseih
Amazon Web Services (AWS)

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