Feedback-ID: ia2694551:Fastmail
Date: Tue, 31 May 2022 11:19:01 +0200
From: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: Michael Paquier <michael@paquier.xyz>
Cc: Andres Freund <andres@anarazel.de>,
	Andrey Borodin <x4mmm@yandex-team.ru>,
	Robert Haas <robertmhaas@gmail.com>, Peter Geoghegan <pg@bowt.ie>,
	=?utf-8?B?0J/QtdGC0YrRgCDQodC70LDQstC+0LI=?= <pet.slavov@gmail.com>,
	PostgreSQL mailing lists <pgsql-bugs@lists.postgresql.org>
Subject: Re: BUG #17485: Records missing from Primary Key index when doing
 REINDEX INDEX CONCURRENTLY
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On 2022-May-31, Michael Paquier wrote:

> Yeah, the tricky part is how to parametize that to be cheap, still
> useful.  Having a larger number of attributes makes the particular
> problem of this thread easier to hit because it enlarges the
> validation window in the concurrent build,

Hmm, I wonder if it's possible to use an index ON tab (pg_sleep(100ms))
or something like that (perhaps even use an expresion involving an
advisory lock acquisition, which is being held by the other session), to
widen the window.

The stop events patch that A. Korotkov posted [0] would likely be very
useful here.

[0] https://postgr.es/m/CAPpHfdtSEOHX8dSk9Qp+Z++i4BGQoffKip6JDWngEA+g7Z-XmQ@mail.gmail.com


> On my own laptop, the original test of the reporter takes up to 3~4s
> to reproduce the issue, for example, all the time, so that's good :)

Sadly, my laptop is somehow broken and I haven't reproduced the failure
even a single time, and my other regular computers are at high seas (I hope).

-- 
Álvaro Herrera        Breisgau, Deutschland  —  https://www.EnterpriseDB.com/