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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
cc: Thomas Munro <thomas.munro@gmail.com>,
        Andrew Dunstan <andrew.dunstan@2ndquadrant.com>,
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Subject: Re: stress test for parallel workers
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Comments: In-reply-to Andres Freund <andres@anarazel.de>
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Andres Freund <andres@anarazel.de> writes:
> Probably requires reproducing on a pretty recent kernel first, to have a
> decent chance of being investigated...

How recent do you think it needs to be?  The machine I was testing on
yesterday is under a year old:

uname -m = ppc64le
uname -r = 4.18.19-100.fc27.ppc64le
uname -s = Linux
uname -v = #1 SMP Wed Nov 14 21:53:32 UTC 2018

The latest-by-version-number ppc64 kernel I can find in the buildfarm
is bonito,

uname -m = ppc64le
uname -r = 4.19.15-300.fc29.ppc64le
uname -s = Linux
uname -v = #1 SMP Mon Jan 14 16:21:04 UTC 2019

and that's certainly shown it too.

			regards, tom lane