MIME-Version: 1.0
References: <abGP87A3JPIXDG2I@nathan>
 <CAA5RZ0tWonKY=E5U51i-J8s2EcRoLqtUQyWv+pQ4_rjFKSn+AA@mail.gmail.com>
 <abGmNAVIPSqX124E@nathan>
 <CAA5RZ0sZE-gfJ0c9HJkOk9XeFQwZL2wuJwrtOX+ZfUBLDcpFMA@mail.gmail.com>
 <abMR6MQGQyyKWep4@nathan>
 <CAApHDvqHXYCb=x0hHeR1e21ksqFNk4q3_zoPk6V-LLu0VL491Q@mail.gmail.com>
 <abrOO8GCgkhMXvcq@nathan>
 <bff7dc5a-f839-449b-b56a-aab36cd3e39d@app.fastmail.com>
 <CAApHDvpnR5zKb7LSB0idj4RPsV+=Dhtk+c5H0cZ4evN2hFDwCQ@mail.gmail.com>
 <3ca1e398-c787-47e9-9afc-8e298b94dac0@app.fastmail.com>
 <abwbDTu6OO6Izp4o@nathan>
In-Reply-To: <abwbDTu6OO6Izp4o@nathan>
From: Sami Imseih <samimseih@gmail.com>
Date: Thu, 19 Mar 2026 23:22:35 -0500
Message-ID: 
 <CAA5RZ0s7k6yve1Bq1OY+aXU3ifc_fvOiYkpE2VxwrUcHr2AtTg@mail.gmail.com>
Subject: Re: another autovacuum scheduling thread
To: Nathan Bossart <nathandbossart@gmail.com>
Cc: Greg Burd <greg@burd.me>, David Rowley <dgrowleyml@gmail.com>,
	Robert Haas <robertmhaas@gmail.com>, Robert Treat <rob@xzilla.net>,
	Jeremy Schneider <schneider@ardentperf.com>,
 pgsql-hackers <pgsql-hackers@postgresql.org>
Content-Type: text/plain; charset="UTF-8"
Archived-At: 
 <https://www.postgresql.org/message-id/CAA5RZ0s7k6yve1Bq1OY%2BaXU3ifc_fvOiYkpE2VxwrUcHr2AtTg%40mail.gmail.com>
Precedence: bulk

> Done in the attached.

Thanks!

I have a few comments.

#1.
+ * between 0.0 and 1.0 (inclusive).  Setting all of these to 0.0 restores

This should be "0.0 and 10.0"

#2.
typo:

+                * being scaling aggressively.

Thisshould be "begin"

#3.
This reads more like documentation than code comment.

+ * To adjust how strongly each component contributes to the score, the
+ * following parameters can be adjusted from their default of 1.0 to anywhere
+ * between 0.0 and 1.0 (inclusive).  Setting all of these to 0.0 restores
+ * pre-v19 prioritization behavior:
+ *
+ *     autovacuum_freeze_score_weight
+ *     autovacuum_multixact_freeze_score_weight
+ *     autovacuum_vacuum_score_weight
+ *     autovacuum_vacuum_insert_score_weight
+ *     autovacuum_analyze_score_weight

I don't actually think this section adds any value at all to the comments.

#4.
+                       elog(DEBUG3, "%s: vac: %.0f (threshold %.0f),
ins: (disabled), anl: %.0f (threshold %.0f), score %.3f",

A missing colon after "score", unlike the other occurrence which has it.

#5.
+               if (autovacuum_freeze_score_weight > 1.0)
+                       effective_xid_failsafe_age /=
autovacuum_freeze_score_weight;
+               if (autovacuum_multixact_freeze_score_weight > 1.0)
+                       effective_mxid_failsafe_age /=
autovacuum_multixact_freeze_score_weight;
+

Shouldn't this be "if (autovacuum_freeze_score_weight > 0.0)" ?
A weight > 0 should always adjust the threshold, right? we should only
prevent division by 0 here.

--
Sami Imseih
Amazon Web Services (AWS)