Re: [PATCH] Improve amcheck to also check UNIQUE constraint in btree index. - Mailing list pgsql-hackers

On Wed, May 1, 2024 at 5:26 AM Alexander Korotkov <aekorotkov@gmail.com> wrote:
> On Wed, May 1, 2024 at 5:24 AM Noah Misch <noah@leadboat.com> wrote:
> > On Thu, Apr 25, 2024 at 04:59:54PM +0400, Pavel Borisov wrote:
> > > 0001: Optimize speed by avoiding heap visibility checking for different
> > > non-deduplicated index tuples as proposed by Noah Misch
> > >
> > > Speed measurements on my laptop using the exact method recommended by Noah
> > > upthread:
> > > Current master branch: checkunique off: 144s, checkunique on: 419s
> > > With patch 0001: checkunique off: 141s, checkunique on: 171s
> >
> > Where is the CPU time going to make it still be 21% slower w/ checkunique on?
> > It's a great improvement vs. current master, but I don't have an obvious
> > explanation for the remaining +21%.
>
> I think there is at least extra index tuples comparison.

The revised patchset is attached.  I applied cosmetical changes.  I'm
going to push it if no objections.

I don't post the patch with rename of new option.  It doesn't seem
there is a consensus.  I must admit that keeping all the options in
the same naming convention makes sense.

------
Regards,
Alexander Korotkov
Supabase