Re: [HACKERS] [PATCH] Make sure all statistics is sent after a fewDML are performed

On Tue, 18 Jul 2017 10:10:49 -0400
Tom Lane <tgl@sss.pgh.pa.us> wrote:

Thank you for your comments. I understand the problem of my proposal
patch.

> Andres Freund <andres@anarazel.de> writes:
> > On 2017-07-18 09:42:31 -0400, Tom Lane wrote:
> >> I wonder if a better answer wouldn't be to reduce PGSTAT_STAT_INTERVAL.
> 
> > Not sure if that really does that much to solve the concern.
> 
> Well, it reduces the amount of data churn that a statement shorter than
> PGSTAT_STAT_INTERVAL could cause.
> 
> > Another,
> > pretty half-baked, approach would be to add a procsignal triggering idle
> > backends to send stats, and send that to all idle backends when querying
> > stats. We could even publish the number of outstanding stats updates in
> > PGXACT or such, without any locking, and send it only to those that have
> > outstanding ones.
> 
> If somebody wanted to do the work, that'd be a viable answer IMO.  You'd
> really want to not wake backends that have nothing more to send, but
> I agree that it'd be possible to advertise that in shared memory.
> 
>             regards, tom lane


-- 
Yugo Nagata <nagata@sraoss.co.jp>