Date: Sun, 2 Apr 2023 14:17:42 -0700
From: Nathan Bossart <nathandbossart@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
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
Message-ID: <20230402211742.GA27239@nathanxps13>
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On Sun, Apr 02, 2023 at 04:23:05PM -0400, Tom Lane wrote:
> 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.

Alright.  I'll change this.

>>> * 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.

Yeah.  I should probably tackle that one first and leave the logical tasks
for later, given there is some prerequisite work required.

-- 
Nathan Bossart
Amazon Web Services: https://aws.amazon.com