On 11/19/2014 08:22 AM, Alvaro Herrera wrote:
>
> I think we're overblowing the pg_upgrade issue. Surely we don't need to
> preserve commit_ts data when upgrading across major versions; and
> pg_upgrade is perfectly prepared to remove old data when upgrading
> (actually it just doesn't copy it; consider pg_subtrans or pg_serial,
> for instance.) If we need to change binary representation in a future
> major release, we can do so without any trouble.
>
That sounds reasonable. I am okay with Petr removing the LSN portion
this patch.