Geert Mak <pobox(at)verysmall(dot)org> wrote:
> yesterday we upgraded 8.x to 9.x
>
> in one table we have nearly 50 million records which are, every
> night, crunched by an insanely complex stored procedure written in
> plpgsql
>
> this takes normally 3 to 3 1/2 hours
>
> after the upgrade it took only 2 hours
>
> do you think this is because 9.x performs better or is it possible
> that our 8.x installation has been muddled up somehow? (we did
> totally clean install/upgrade with drop/import)
8.x covers five major releases with some very important performance
improvements from one to the next. 9.x covers two major production
releases and a new major release in beta testing. So, if you went
from 8.0 to 9.1 I'd be surprised not to see a much bigger
improvement. If you went from 8.4 to 9.0 it might have been at
least partly a matter of the conversion eliminating some bloat.
http://www.postgresql.org/support/versioning/
-Kevin