Horton

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

Alexander Korotkov <aekorotkov@gmail.com>

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From: Alexander Korotkov <aekorotkov@gmail.com>
To: Noah Misch <noah@leadboat.com>
Cc: Pavel Borisov <pashkin.elfe@gmail.com>, Peter Eisentraut <peter@eisentraut.org>, Aleksander Alekseev <aleksander@timescale.com>, Postgres hackers <pgsql-hackers@lists.postgresql.org>, Maxim Orlov <orlovmg@gmail.com>, Andres Freund <andres@anarazel.de>, Greg Stark <stark@mit.edu>, Julien Rouhaud <rjuju123@gmail.com>, Mark Dilger <mark.dilger@enterprisedb.com>, David Steele <david@pgmasters.net>, Peter Geoghegan <pg@bowt.ie>, Maxim Orlov <m.orlov@postgrespro.ru>, lubennikovaav@gmail.com
Date: 2024-05-10T00:11:41Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. amcheck: Optimize speed of checking for unique constraint violation

  2. amcheck: Report an error when the next page to a leaf is not a leaf

  3. amcheck: Don't load the right sibling page into BtreeCheckState

  4. amcheck: Refactoring the storage of the last visible entry

  5. Teach contrib/amcheck to check the unique constraint violation

  6. Add macros in hash and btree AMs to get the special area of their pages

Attachments

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