Re: pgsql: pg_upgrade: Convert old visibility map format to new format.

On Fri, Mar 11, 2016 at 05:36:34PM +0000, Robert Haas wrote:
> pg_upgrade: Convert old visibility map format to new format.
>
> Commit a892234f830e832110f63fc0a2afce2fb21d1584 added a second bit per
> page to the visibility map, but pg_upgrade has been unaware of it up
> until now.  Therefore, a pg_upgrade from an earlier major release of
> PostgreSQL to any commit preceding this one and following the one
> mentioned above would result in invalid visibility map contents on the
> new cluster, very possibly leading to data corruption.  This plugs
> that hole.
>
> Masahiko Sawada, reviewed by Jeff Janes, Bruce Momjian, Simon Riggs,
> Michael Paquier, Andres Freund, me, and others.

I have tested the current git trees of all supported versions of
Postgres in all possible pg_upgrade combinations and they all worked
perfectly.

--
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

+ As you are, so once was I. As I am, so you will be. +
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