Date: Mon, 13 Jan 2025 13:50:39 -0600
From: Nathan Bossart <nathandbossart@gmail.com>
To: Thomas Munro <thomas.munro@gmail.com>
Cc: pgsql-hackers@postgresql.org
Subject: Re: connection establishment versus parallel workers
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On Thu, Dec 19, 2024 at 10:09:35AM -0600, Nathan Bossart wrote:
> On Fri, Dec 13, 2024 at 03:56:00PM +1300, Thomas Munro wrote:
>> 0001 patch is unchanged, 0002 patch sketches out a response to the
>> observation a couple of paragraphs above.
> 
> Both of these patches seem to improve matters quite a bit.  I haven't yet
> thought too deeply about it all, but upon a skim, your patches seem
> entirely reasonable to me.

I gave these a closer look, and I still feel that they are both
straightforward and reasonable.  IIUC the main open question is whether
this might cause problems for other PM signal kinds.  Like you, I don't see
anything immediately obvious there, but I'll admit I'm not terribly
familiar with the precise characteristics of postmaster signals.  In any
case, 0001 feels pretty safe to me.

> However, while this makes the test numbers for >= v16 look more like those
> for v15, we're also seeing a big jump from v13 to v14.  This bisects pretty
> cleanly to commit d872510.  I haven't figured out _why_ this commit is
> impacting this particular test, but I figured I'd at least update the
> thread with what we know so far.

I regrettably have no updates on this one, yet.

-- 
nathan