Re: Further pg_upgrade analysis for many tables
Bruce Momjian <bruce@momjian.us>
From: Bruce Momjian <bruce@momjian.us>
To: Jeff Janes <jeff.janes@gmail.com>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>, Magnus Hagander <magnus@hagander.net>
Date: 2012-11-10T17:18:11Z
Lists: pgsql-hackers
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. +