Date: Sat, 2 Jul 2022 15:05:54 -0700
From: Nathan Bossart <nathandbossart@gmail.com>
To: Simon Riggs <simon.riggs@enterprisedb.com>
Cc: Robert Haas <robertmhaas@gmail.com>, Andres Freund <andres@anarazel.de>,
	"Bossart, Nathan" <bossartn@amazon.com>,
	Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.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: <20220702220554.GA1044460@nathanxps13>
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On Fri, Jun 24, 2022 at 11:45:22AM +0100, Simon Riggs wrote:
> On Thu, 23 Jun 2022 at 18:15, Nathan Bossart <nathandbossart@gmail.com> wrote:
>> I'm grateful for the discussion in this thread so far, but I'm not seeing a
>> clear path forward.
> 
> +1 to add the new auxiliary process.

I went ahead and put together a new patch set for this in which I've
attempted to address most of the feedback from upthread.  Notably, I've
abandoned 0007 and 0008, added a way for processes to request specific
tasks for the custodian, and removed all the checks for
ShutdownRequestPending.

I haven't addressed the existing transaction ID wraparound risk with the
logical replication files.  My instinct is that this deserveѕ its own
thread, and it might need to be considered a prerequisite to this change
based on the prior discussion here.

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

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