Re: buildfarm: could not read block 3 in file "base/16384/2662": read only 0 of 8192 bytes

Andres Freund <andres@anarazel.de> writes:
> On 2018-08-29 12:56:07 -0400, Tom Lane wrote:
>> BTW, I now have a theory for why we suddenly started seeing this problem
>> in mid-June: commits a54e1f158 et al added a ScanPgRelation call where
>> there had been none before (in RelationReloadNailed, for non-index rels).
>> That didn't create the problem, but it probably increased the odds of
>> seeing it happen.

> Yea.  Doesn't explain why it's only really visible on the BF in
> 11/master though :/

Probably we changed around the tests that run in parallel with vacuum.sql
enough during v11 to make it happen with noticeable probability.  I think
this is sufficient evidence that it's happening now in the back branches:

https://www.postgresql.org/message-id/20180829140149.GO23024@telsasoft.com

            regards, tom lane