Re: Pathological performance when inserting many NULLs into a unique index

From: Michael Paquier <michael(at)paquier(dot)xyz>
To: Peter Geoghegan <pg(at)bowt(dot)ie>
Cc: PostgreSQL Hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: Pathological performance when inserting many NULLs into a unique index
Date: 2019-04-19 00:46:13
Message-ID: 20190419004613.GE2660@paquier.xyz
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On Wed, Apr 17, 2019 at 07:37:17PM -0700, Peter Geoghegan wrote:
> I'll create an open item for this, and begin work on a patch tomorrow.

Adding an open item is adapted, nice you found this issue. Testing on
my laptop with v11, the non-NULL case takes 5s and the NULL case 6s.
On HEAD, the non-NULL case takes 6s, and the NULL case takes... I
just gave up and cancelled it :)
--
Michael

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