Re: pg_upgrade < 9.3 -> >=9.3 misses a step around multixacts

Alvaro Herrera wrote:
> Bruce Momjian wrote:

> Bruce Momjian wrote:
>
> > > OK, so the xid has to be beyond 2^31 during pg_upgrade to trigger a
> > > problem? That might explain the rare reporting of this bug. What would
> > > the test query look like so we can tell people when to remove the '0000'
> > > files? Would we need to see the existence of '0000' and high-numbered
> > > files? How high? What does a 2^31 file look like?
> >
> > Also, what would a legitimate 0000 file at wrap-around time look like?
> > Would there have to be an 'ffff' or 'ffffff' file?
>
> Since I was wrong, there is no point in further research here. Anyway
> the last file before wrapping around in pg_multixact/members is FFFF.

Oops, I meant the last file before wrap in pg_multixact/offsets is FFFF,
which is what we're talking about in this thread.

For members it's 14078, but it's not relevant here.

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