Re: Suppressing useless wakeups in walreceiver

On Mon, Nov 14, 2022 at 12:51:14PM +1300, Thomas Munro wrote:
> On Mon, Nov 14, 2022 at 12:35 PM Thomas Munro <thomas.munro@gmail.com> wrote:
>> Maybe there is a better way to code this (I mean, who likes global
>> variables?) and I need to test some more, but I suspect the attached
>> is approximately what we missed.
> 
> Erm, ENOCOFFEE, sorry that's not quite right, it needs the apply LSN,
> but it demonstrates what the problem is...

Yeah, I'm able to sort-of reproduce the problem by sending fewer replies,
but it's not clear to me why that's the problem.  AFAICT all of the code
paths that write/flush are careful to send a reply shortly afterward, which
should keep writePtr/flushPtr updated.

-- 
Nathan Bossart
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