Re: pg_upgrade with -j shows no perf improvement

On Mon, Jun 17, 2013 at 10:26:48AM -0700, Lonni J Friedman wrote:
> >> I only have 1 tablespace, although I have 9 databases. However, one
> >> of the databases is about 95% of the total on-disk space, so that's
> >> probably the explanation of why -j isn't helping me?
> >>
> >
> > That is probably why you DID had some improvement, although so little.

Agreed.

> >> I don't have sufficient disk space to efficiently test --link mode,
> >> unless there's some way to quickly roll back to the pre-upgrade
> >> version of the database after a --link mode upgrade has completed
> >> successfully that I'm not seeing?
> >>
> >
> > I didn't got it. AFAIK, in link mode it would take **less** space than
> > normal mode, not the opposite. Am I wrong?
>
> No, you're correct, but I want to keep the old version unchanged after
> the upgrade. I didn't think that was possible with link mode.

It is not possible in link mode if you start the new cluster. If you
don't start the new cluster, you can just delete the new cluster and
restart the unchanged old cluster, thought you have to remove the .old
suffix on the control file.

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com

+ It's impossible for everything to be true. +