Date: Tue, 29 Nov 2022 21:04:41 -0800
From: Nathan Bossart <nathandbossart@gmail.com>
To: Thomas Munro <thomas.munro@gmail.com>
Cc: "Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>,
	"pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
Subject: Re: wake up logical workers after ALTER SUBSCRIPTION
Message-ID: <20221130050441.GA1677223@nathanxps13>
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On Wed, Nov 30, 2022 at 05:27:40PM +1300, Thomas Munro wrote:
> On Wed, Nov 30, 2022 at 5:23 PM Thomas Munro <thomas.munro@gmail.com> wrote:
>> On Wed, Nov 30, 2022 at 5:10 PM Nathan Bossart <nathandbossart@gmail.com> wrote:
>> > I spent some more time on the prevent-unnecessary-wakeups patch for
>> > logical/worker.c that I've been alluding to in this thread, and I found a
>> > few more places where we depend on the worker periodically waking up.  This
>> > seems to be a common technique, so I'm beginning to wonder whether these
>> > changes are worthwhile.  I think there's a good chance it would become a
>> > game of whac-a-mole.
>>
>> Aren't they all bugs, though, making our tests and maybe even real
>> systems slower than they need to be?

Yeah, you're right, it's probably worth proceeding with this particular
thread even if we don't end up porting the suppress-unnecessary-wakeups
patch to logical/worker.c.

> (Which isn't to suggest that it's your job to fix them, but please do
> share what you have if you run out of whack-a-mole steam, since we
> seem to have several people keen to finish those moles off.)

I don't mind fixing it!  There are a couple more I'd like to track down
before posting another revision.

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