Re: Issues with Quorum Commit

*

On 10/8/10, Fujii Masao <masao(dot)fujii(at)gmail(dot)com> wrote:
> On Fri, Oct 8, 2010 at 5:10 PM, Heikki Linnakangas
> <heikki(dot)linnakangas(at)enterprisedb(dot)com> wrote:
>> Do we really need that?
>
> Yes. But if there is no unsent WAL when the master goes down,
> we can start new standby without new backup by copying the
> timeline history file from new master to new standby and
> setting recovery_target_timeline to 'latest'. In this case,
> new standby advances the recovery to the latest timeline ID
> which new master uses before connecting to the master.
>
> This seems to have been successful in my test environment.
> Though I'm missing something.
>
>> I don't think that's acceptable, we'll need to fix
>> that if that's the case.
>
> Agreed.
>
>> You can cross timelines with the archive, though. But IIRC there was some
>> issue with that too, you needed to restart the standbys because the
>> standby
>> scans what timelines exist at the beginning of recovery, and won't notice
>> new timelines that appear after that?
>
> Yes.
>
>> We need to address that, apart from any of the other things discussed wrt.
>> synchronous replication. It will benefit asynchronous replication too.
>> IMHO
>> *that* is the next thing we should do, the next patch we commit.
>
> You mean to commit that capability before synchronous replication? If so,
> I disagree with you. I think that it's not easy to address that problem.
> So I'm worried about that implementing that capability first means the miss
> of sync rep in 9.1.
>
> Regards,
>
> --
> Fujii Masao
> NIPPON TELEGRAPH AND TELEPHONE CORPORATION
> NTT Open Source Software Center
>
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--
Rob Wultsch
wultsch(at)gmail(dot)com