Re: Re: PANIC: invalid index offnum: 186 when processing BRIN indexes in VACUUM

On 10/30/2017 09:03 PM, Tom Lane wrote:
> Michael Paquier <michael(dot)paquier(at)gmail(dot)com> writes:
>> b1328d78f is close enough, but per what I see that's actually not
>> true. I have been able to reproduce the problem, which shows up within
>> a window of 2-4 minutes. Still sometimes it can take way longer, and I
>> spotted one test where it took 15 minutes to show up... So, bisecting
>> with a test that looks for core files for 20 minutes, I am seeing that
>> the following commit is actually at fault:
>
>> commit 24992c6db9fd40f342db1f22747ec9e56483796d
>> Author: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
>> Date: Fri Sep 9 19:00:59 2016 -0400
>
>> Rewrite PageIndexDeleteNoCompact into a form that only deletes 1 tuple.
>
> [ scratches head ... ] Not sure how that could've introduced any
> problems? Will look.
>

Not sure, but I can confirm Michael's findings - I've been unable to
reproduce the issue on 1a4be103a5 even after 20 minutes, and on
24992c6db9 it failed after only 2.

regards

--
Tomas Vondra http://www.2ndQuadrant.com
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