Re: track_commit_timestamp and COMMIT PREPARED

On 2015-09-29 05:05, Alvaro Herrera wrote:
> Petr Jelinek wrote:
>> On 2015-09-02 16:14, Fujii Masao wrote:
>>> On Wed, Aug 5, 2015 at 2:16 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>>>> On Mon, Aug 3, 2015 at 10:31 AM, Fujii Masao <masao(dot)fujii(at)gmail(dot)com> wrote:
>>>>> track_commit_timestamp tracks COMMIT PREPARED as expected in standby server,
>>>>> but not in master server. Is this intentional? It should track COMMIT PREPARED
>>>>> even in master? Otherwise, we cannot use commit_timestamp feature to check
>>>>> the replication lag properly while we use 2PC.
>>>>
>>>> That sounds like it must be a bug. I think you should add it to the
>>>> open items list.
>>
>> Attached fixes this. It includes advancement of replication origin as well.
>> I didn't feel like doing refactor of commit code this late in 9.5 cycle
>> though, so I went with the code duplication + note in xact.c.
>
> Thanks, your proposed behavior looks reasonable. I didn't like the
> existing coding nor the fact that with your patch we'd have two copies
> of it, so I changed a bit instead to be more understandable. Hopefully I
> didn't break too many things. This patch includes the patch for the
> other commitTS open item too.
>

Looks good. It does change the logic slightly - previous code didn't
advance session origin lsn if origin timestamp wasn't set, your code
does, but I think the new behavior is better.

--
Petr Jelinek http://www.2ndQuadrant.com/
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