| From: | Dimitri Fontaine <dimitri(at)2ndQuadrant(dot)fr> |
|---|---|
| To: | hlinnaka(at)iki(dot)fi |
| Cc: | Fujii Masao <masao(dot)fujii(at)gmail(dot)com>, Simon Riggs <simon(at)2ndquadrant(dot)com>, PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: Cascading replication and recovery_target_timeline='latest' |
| Date: | 2012-09-05 08:03:47 |
| Message-ID: | m2wr08vqu4.fsf@2ndQuadrant.fr |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
Heikki Linnakangas <hlinnaka(at)iki(dot)fi> writes:
> On 04.09.2012 03:02, Dimitri Fontaine wrote:
>> Heikki Linnakangas<hlinnaka(at)iki(dot)fi> writes:
>>> Hmm, I was thinking that when walsender gets the position it can send the
>>> WAL up to, in GetStandbyFlushRecPtr(), it could atomically check the current
>>> recovery timeline. If it has changed, refuse to send the new WAL and
>>> terminate. That would be a fairly small change, it would just close the
>>> window between requesting walsenders to terminate and them actually
>>> terminating.
>
> No, only cascading replication is affected. In non-cascading situation, the
> timeline never changes in the master. It's only in cascading mode that you
> have a problem, where the standby can cross timelines while it's replaying
> the WAL, and also sending it over to cascading standby.
It seems to me that it applies to connecting a standby to a newly
promoted standby too, as the timeline did change in this case too.
Regards,
--
Dimitri Fontaine
http://2ndQuadrant.fr PostgreSQL : Expertise, Formation et Support
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Albe Laurenz | 2012-09-05 08:16:19 | Re: State of the on-disk bitmap index |
| Previous Message | Vik Reykja | 2012-09-05 07:50:44 | Re: 9.2rc1 produces incorrect results |