Date: Wed, 1 Dec 2021 14:56:32 -0800
From: Andres Freund <andres@anarazel.de>
To: "Bossart, Nathan" <bossartn@amazon.com>
Cc: "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Subject: Re: O(n) tasks cause lengthy startups and checkpoints
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Hi,

On 2021-12-01 20:24:25 +0000, Bossart, Nathan wrote:
> I realize adding a new maintenance worker might be a bit heavy-handed,
> but I think it would be nice to have somewhere to offload tasks that
> really shouldn't impact startup and checkpointing.  I imagine such a
> process would come in handy down the road, too.  WDYT?

-1. I think the overhead of an additional worker is disproportional here. And
there's simplicity benefits in having a predictable cleanup interlock as well.

I think particularly for the snapshot stuff it'd be better to optimize away
unnecessary snapshot files, rather than making the cleanup more asynchronous.

Greetings,

Andres Freund