From: Tom Lane <tgl@sss.pgh.pa.us>
To: Nathan Bossart <nathandbossart@gmail.com>
cc: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>,
        Robert Haas <robertmhaas@gmail.com>,
        Andres Freund <andres@anarazel.de>,
        "Bossart,
    Nathan" <bossartn@amazon.com>,
        Maxim Orlov <orlovmg@gmail.com>, Amul Sul <sulamul@gmail.com>,
        Bruce Momjian <bruce@momjian.us>,
        "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Subject: Re: O(n) tasks cause lengthy startups and checkpoints
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Comments: In-reply-to Nathan Bossart <nathandbossart@gmail.com>
	message dated "Sun, 02 Apr 2023 12:30:30 -0700"
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Date: Sun, 02 Apr 2023 16:23:05 -0400
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Nathan Bossart <nathandbossart@gmail.com> writes:
> On Sun, Apr 02, 2023 at 01:40:05PM -0400, Tom Lane wrote:
>> * Why does LookupCustodianFunctions think it needs to search the
>> constant array?

> The order of the tasks in the array isn't guaranteed to match the order in
> the CustodianTask enum.

Why not?  It's a constant array, we can surely manage to make its
order match the enum.

>> * The original proposal included moving RemovePgTempFiles into this
>> mechanism, which I thought was probably the most useful bit of the
>> whole thing.  I'm sad to see that gone, what became of it?

> I postponed that based on advice from upthread [1].  I was hoping to start
> a dedicated thread for that immediately after the custodian infrastructure
> was committed.  FWIW I agree that it's the most useful task of what's
> proposed thus far.

Hmm, given Andres' objections there's little point in moving forward
without that task.

			regards, tom lane