Horton

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

Noah Misch <noah@leadboat.com>

View thread
From: Noah Misch <noah@leadboat.com>
To: Pavel Borisov <pashkin.elfe@gmail.com>
Cc: Alexander Korotkov <aekorotkov@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: 2024-05-01T02:24:12Z
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

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%.