Re: [PATCH] Improve amcheck to also check UNIQUE constraint in btree index.

Hi Noah,

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.

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Regards,
Alexander Korotkov