From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: pgsql-hackers@lists.postgresql.org
Subject: Re: pgsql: aio: Infrastructure for io_method=worker
In-reply-to: <27fwadt6whe5ufqyrgbrnu3ppfiocaljtt3fufedn6sclvjqll@kotindcvgtoy>
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Comments: In-reply-to Andres Freund <andres@anarazel.de>
	message dated "Tue, 18 Mar 2025 19:07:53 -0400"
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Date: Tue, 18 Mar 2025 21:24:16 -0400
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Andres Freund <andres@anarazel.de> writes:
> On 2025-03-18 18:53:48 -0400, Tom Lane wrote:
>> I wonder though if we ought to revert 38da05346 and/or 6d0154196 in vie=
w of
>> that.

> 38da05346 doesn't seem to have much value if it doesn't help us run the =
tests
> by default - but it also doesn't really hurt. So, shrug, I guess.

> 6d0154196 - a higher autovacuum_worker_slots increases resource usage mo=
re
> than IO workers do, because autovac workers are included in computations=
 like
> lock space. But 16 isn't that much either way...

IMV the argument for reverting either would basically be simplicity.
It's not even so much the code, as the comments defending these odd
looking choices.  Future hackers will read those and wonder if the
arguments still apply --- and the answer will be "no".

38da05346 was back-patched into 17, and I'd leave it as-is there,
since it was holding the line on "can start with 60 semaphores"
for that branch.  But once we've lost that battle, it's hard to
see what it's doing for us.

			regards, tom lane