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From: Tom Lane <tgl@sss.pgh.pa.us>
To: pgsql-hackers@lists.postgresql.org
Subject: PANIC: wrong buffer passed to visibilitymap_clear
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Date: Fri, 09 Apr 2021 18:40:27 -0400
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Buildfarm members spurfowl[1] and thorntail[2] have each shown $SUBJECT
once in the past two days.  The circumstances are not quite the same;
spurfowl's failure is in autovacuum while thorntail's is in a manual
VACUUM command.  Still, it seems clear that there's a recently-introduced
bug here somewhere.  I don't see any obvious candidate for the culprit,
though.  Any ideas?

			regards, tom lane

[1] https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=3Dspurfowl&dt=3D=
2021-04-08%2010%3A22%3A08
[2] https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=3Dthorntail&dt=
=3D2021-04-09%2021%3A28%3A10