Re: Inconsistency in reporting checkpointer stats

At Wed, 21 Dec 2022 17:14:12 +0530, Nitin Jadhav <nitinjadhavpostgres(at)gmail(dot)com> wrote in
> [1]:
> 2022-12-21 10:52:25.931 UTC [63530] LOG: checkpoint complete: wrote
> 4670 buffers (28.5%), wrote 3 slru buffers (0.0%); 0 WAL file(s)
> added, 0 removed, 4 recycled; write=0.045 s, sync=0.161 s, total=0.244
> s; sync files=25, longest=0.146 s, average=0.007 s; distance=66130 kB,
> estimate=66130 kB; lsn=0/5557C78, redo lsn=0/5557C40
>
> Thanks & Regards,
> Nitin Jadhav
>
> On Tue, Dec 20, 2022 at 11:08 PM Andres Freund <andres(at)anarazel(dot)de> wrote:
> >
> > On 2022-12-20 08:18:36 -0500, Robert Haas wrote:
> > > I think that the SLRU information is potentially useful, but mixing it
> > > with the information about regular buffers just seems confusing.
> >
> > +1
> >
> > At least for now, it'd be different if/when we manage to move SLRUs to
> > the main buffer pool.

It sounds reasonable to exclude SRLU write from buffer writes. But I'm
not sure its useful to count SLRU writes separately since it is under
the noise level of buffer writes in reglular cases and the value
doesn't lead to tuning. However I'm not strongly opposed to adding it
either.

regards.

--
Kyotaro Horiguchi
NTT Open Source Software Center