Re: performance penalty between Postgresql 8.3.8 and 8.4.1

Hi David,

On Tuesday 08 December 2009 10:59:51 Schmitz, David wrote:
> >> With our data it is a performance difference from 1h16min
> >> (8.3.8) to 2h43min (8.4.1)
> On Postgresql 8.4.1
> Total runtime: 101.446 ms
> and on Postgresql  8.3.8:
> Total runtime: 29.366 ms
Hm. There obviously is more going on than these queries?

> Hash Join  (cost=2603.57..124518.03 rows=60772 width=61) (actual
time=62.359..97.268 rows=1444 loops=1)
> Nested Loop  (cost=21.00..3790.18 rows=81 width=61) (actual
time=0.210..26.098 rows=1444 loops=1)
Both misestimate the resultset quite a bit. It looks like happenstance that
the one on 8.3 turns out to be better...

Andres