From: | Simon Riggs <simon(at)2ndQuadrant(dot)com> |
---|---|
To: | Fujii Masao <masao(dot)fujii(at)gmail(dot)com> |
Cc: | Heikki Linnakangas <heikki(dot)linnakangas(at)enterprisedb(dot)com>, PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org> |
Subject: | Re: Streaming replication and pg_xlogfile_name() |
Date: | 2010-02-25 09:33:30 |
Message-ID: | 1267090410.3752.7413.camel@ebony |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
On Thu, 2010-02-25 at 12:02 +0900, Fujii Masao wrote:
> On Wed, Feb 24, 2010 at 7:56 AM, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> > On Thu, 2010-01-28 at 10:28 +0200, Heikki Linnakangas wrote:
> >> Fujii Masao wrote:
> >> > In relation to the functions added recently, I found an annoying problem;
> >> > pg_xlogfile_name(pg_last_xlog_receive/replay_location()) might report the
> >> > wrong name because pg_xlogfile_name() always uses the current timeline,
> >> > and a backend doesn't know the actual timeline related to the location
> >> > which pg_last_xlog_receive/replay_location() reports. Even if a backend
> >> > knows that, pg_xlogfile_name() would be unable to determine which timeline
> >> > should be used.
> >>
> >> Hmm, I'm not sure what the use case for this is
> >
> > Agreed. What is the use case for this?
>
> Since the current behavior would annoy many users (e.g., [*1]),
> I proposed to change it.
>
> [*1]
> http://archives.postgresql.org/pgsql-hackers/2010-02/msg02014.php
OK, go for it.
If we expose the timeline as part of an "xlog location", then we should
do that everywhere as a change for 9.0. Clearly, "xlog location" has no
meaning without the timeline anyway, so this seems like a necessary
change not just a quick fix. It breaks compatibility, but since we're
changing replication in 9.0 that shouldn't be a problem.
--
Simon Riggs www.2ndQuadrant.com
From | Date | Subject | |
---|---|---|---|
Next Message | Heikki Linnakangas | 2010-02-25 09:35:30 | Odd CVS revision number |
Previous Message | Fujii Masao | 2010-02-25 09:25:48 | Re: testing cvs HEAD - HS/SR - xlog timeline 0 pg_xlogfile_name_offset |