Re: Immediate standby promotion

On Thu, Sep 25, 2014 at 11:34 AM, Andres Freund <andres@2ndquadrant.com> wrote:
> On 2014-09-25 11:13:50 -0400, Robert Haas wrote:
>> On Wed, Sep 24, 2014 at 4:36 PM, Simon Riggs <simon@2ndquadrant.com> wrote:
>> >> To me, being able to say "pg_ctl promote_right_now -m yes_i_mean_it"
>> >> seems like a friendlier interface than making somebody shut down the
>> >> server, run pg_resetxlog, and start it up again.
>> >
>> > It makes sense to go from paused --> promoted.
>>
>> Well, we could certainly require that people call
>> pg_xlog_replay_pause() before they call pg_promote_now().  I don't
>> think I like that better, but it beats not having pg_promote_now().
>
> FWIW I think it's a mistake to only allow this on a hot standby. This
> should be doable using pg_ctl alone. a) works with wal_level=archive, b)
> sometimes hot_standby=off is a good bit more efficient c) sometimes you
> don't want to allow connections.

Good point.  Also, a pg_ctl command is more friendly to cluster-ware,
of which there is a lot these days.

-- 
Robert Haas
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