Feedback-ID: id4a34324:Fastmail
Date: Thu, 7 Nov 2024 16:38:09 -0500
From: Andres Freund <andres@anarazel.de>
To: Jan Wieck <jan@wi3ck.info>
Cc: Amit Kapila <amit.kapila16@gmail.com>, 
	Aleksander Alekseev <aleksander@timescale.com>, pgsql-hackers <pgsql-hackers@postgresql.org>, 
	shveta malik <shveta.malik@gmail.com>, "Zhijie Hou (Fujitsu)" <houzj.fnst@fujitsu.com>, tomas@vondra.me
Subject: Re: Commit Timestamp and LSN Inversion issue
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Hi,

On 2024-11-07 15:05:31 -0500, Jan Wieck wrote:
> On 11/7/24 13:19, Andres Freund wrote:
> > I think it's *completely* unacceptable to call a hook inside
> > ReserveXLogInsertLocation, with the spinlock held, no less. That's the most
> > contended section of code in postgres.
> 
> Aside from your technical concerns, can we at least agree that the commit-ts
> vs LSN inversion is a problem that should get addressed?

I'm not against addressing it, but I'd consider it not a high priority and
that the acceptable cost (both runtime and maintenance) of it should would
need to be extremely low.

Greetings,

Andres Freund