Re: GUC for cleanup indexes threshold.

I was just looking the thread since it is found left alone for a
long time in the CF app.

At Mon, 18 Sep 2017 16:35:58 -0700, Peter Geoghegan <pg(at)bowt(dot)ie> wrote in <CAH2-WzkhJhAXD+6DdBp7D8WYLfJ3D0m=AZbGsiw=USUjTmuv-g(at)mail(dot)gmail(dot)com>
> On Wed, Apr 5, 2017 at 3:50 PM, Andres Freund <andres(at)anarazel(dot)de> wrote:
> > Hi,
> >
> > On 2017-04-01 03:05:07 +0900, Masahiko Sawada wrote:
> >> On Fri, Mar 31, 2017 at 11:44 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> >> [ lots of valuable discussion ]
> >
> > I think this patch clearly still is in the design stage, and has
> > received plenty feedback this CF. I'll therefore move this to the next
> > commitfest.
>
> Does anyone have ideas on a way forward here? I don't, but then I
> haven't thought about it in detail in several months.

Is the additional storage in metapage to store the current status
of vaccum is still unacceptable even if it can avoid useless
full-page scan on indexes especially for stable tables?

Or, how about additional 1 bit in pg_stat_*_index to indicate
that the index *don't* require vacuum cleanup stage. (default
value causes cleanup)

index_bulk_delete (or ambulkdelete) returns the flag in
IndexBulkDeleteResult then lazy_scan_heap stores the flag in
stats and in the next cycle it is looked up to decide the
necessity of index cleanup.

regards,

--
Kyotaro Horiguchi
NTT Open Source Software Center