Re: Resetting spilled txn statistics in pg_stat_replication

On Tue, 2 Jun 2020 at 18:34, Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
>
> On Tue, Jun 2, 2020 at 11:48 AM Masahiko Sawada
> <masahiko(dot)sawada(at)2ndquadrant(dot)com> wrote:
> >
> > Hi all,
> >
> > Tracking of spilled transactions has been introduced to PG13. These
> > new statistics values, spill_txns, spill_count, and spill_bytes, are
> > cumulative total values unlike other statistics values in
> > pg_stat_replication. How can we reset these values? We can reset
> > statistics values in other statistics views using by
> > pg_stat_reset_shared(), pg_stat_reset() and so on. It seems to me that
> > the only option to reset spilled transactions is to restart logical
> > replication but it's surely high cost.
> >
>
> I see your point but I don't see a pressing need for such a function
> for PG13. Basically, these counters will be populated when we have
> large transactions in the system so not sure how much is the use case
> for such a function. Note that we need to add additional column
> stats_reset in pg_stat_replication view as well similar to what we
> have in pg_stat_archiver and pg_stat_bgwriter. OTOH, I don't see any
> big reason for not having such a function for PG14.

Ok. I think the reset function is mostly for evaluations or rare
cases. In either case, since it's not an urgent case we can postpone
it to PG14 if necessary.

Regards,

--
Masahiko Sawada http://www.2ndQuadrant.com/
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