Re: pg_logical_emit_message() misses a XLogFlush() - Mailing list pgsql-hackers

From Andres Freund
Subject Re: pg_logical_emit_message() misses a XLogFlush()
Date
Msg-id 20230816003333.7hn2rx5m2l7una3d@awork3.anarazel.de
Whole thread Raw
In response to Re: pg_logical_emit_message() misses a XLogFlush()  (Michael Paquier <michael@paquier.xyz>)
Responses Re: pg_logical_emit_message() misses a XLogFlush()
List pgsql-hackers
Hi,

On 2023-08-16 06:58:56 +0900, Michael Paquier wrote:
> On Tue, Aug 15, 2023 at 11:37:32AM +0200, Tomas Vondra wrote:
> > Shouldn't the flush be done only for non-transactional messages? The
> > transactional case will be flushed by regular commit flush.
> 
> Indeed, that would be better.  I am sending an updated patch.
> 
> I'd like to backpatch that, would there be any objections to that?

Yes, I object. This would completely cripple the performance of some uses of
logical messages - a slowdown of several orders of magnitude. It's not clear
to me that flushing would be the right behaviour if it weren't released, but
it certainly doesn't seem right to make such a change in a minor release.

Greetings,

Andres Freund



pgsql-hackers by date:

Previous
From: Peter Smith
Date:
Subject: Re: [PATCH] Reuse Workers and Replication Slots during Logical Replication
Next
From: Richard Guo
Date:
Subject: Re: Test case for parameterized remote path in postgres_fdw