Re: Standby catch up state change - Mailing list pgsql-hackers

From Pavan Deolasee
Subject Re: Standby catch up state change
Date
Msg-id 379CE38B-C498-4675-8083-E7879663F355@gmail.com
Whole thread Raw
In response to Re: Standby catch up state change  (Andres Freund <andres@2ndquadrant.com>)
List pgsql-hackers

> On 16-Oct-2013, at 3:45 pm, Andres Freund <andres@2ndquadrant.com> wrote:
>
>> On 2013-10-16 11:03:12 +0530, Pavan Deolasee wrote:
>> I think you are right. Someone who understands the replication code very
>> well advised us to use that log message as a way to measure how much time
>> it takes to send all the missing WAL to a remote standby on a slow WAN
>> link. While it worked well for all measurements, when we use a middleware
>> which caches a lot of traffic on the sender side, this log message was very
>> counter intuitive. It took several more minutes for the standby to actually
>> receive all the WAL files and catch up after the message was displayed on
>> the master side. But then as you said, may be relying on the message was
>> not the best way to measure the time.
>
> Query pg_stat_replication instead, that has the flush position.
>

Yeah, that's what we are doing now.

Thanks,
Pavan

> Greetings,
>
> Andres Freund
>
> --
> Andres Freund                       http://www.2ndQuadrant.com/
> PostgreSQL Development, 24x7 Support, Training & Services



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