Re: found xmin from before relfrozenxid on pg_catalog.pg_authid

On 2018-May-24, Andres Freund wrote:

> On 2018-05-24 16:49:40 -0400, Alvaro Herrera wrote:
> > BTW is it just a coincidence or are all the affected tables pg_authid?
> > Maybe the problem is shared relations ..? Maybe the fact that they have
> > separate relfrozenxid (!?) in different databases?
>
> Yes, that appears to be part of the problem. I've looked at a number of
> shared relation related codepaths, but so far my theory is that the
> relcache is wrong. Note that one of the reports in this thread clearly
> had a different relcache relfrozenxid than in the catalog.

Hmm ... is that because they read the values on different databases?
Are you referring to the reports by Maxim Boguk? I see one value from
template1, another value from template0.

> Then there's also:
> http://archives.postgresql.org/message-id/1527193504642.36340%40amazon.com

ah, so deleting the relcache file makes the problem to go away? That's
definitely pretty strange. I see no reason for the value in relcache to
become out of step with the catalogued value in the same database ... I
don't think we transmit in any way values of one database to another.

--
Álvaro Herrera https://www.2ndQuadrant.com/
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