Re: Further pg_upgrade analysis for many tables

On Fri, Nov  9, 2012 at 04:23:40PM -0800, Jeff Janes wrote:
> > Actually, pg_upgrade needs pg_dump to restore all those sequence values.
> 
> I did an experiment where I had pg_dump just output dummy values
> rather than hitting the database.  Once pg_upgrade moves the relation
> files over, the dummy values disappear and are set back to their
> originals.  So I think that pg_upgrade depends on pg_dump only in a
> trivial way--they need to be there, but it doesn't matter what they
> are.

FYI, thanks everyone for testing this.  I will keep going on my tests
--- seems I have even more things to try in my benchmarks.  I will
publish my results soon.

In general, I think we are getting some complaints about dump/restore
performance with a large number of tables, irregardless of pg_upgrade,
so it seems worthwhile to try to find the cause.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + It's impossible for everything to be true. +