Re: Performance differences 7.1 to 7.3

On Mon, 2004-12-13 at 17:43 -0500, Jimmie H. Apsey wrote:
> Hello all,
> I have just loaded Postgresql 7.3.6-7 onto a new server on the
> recommendation of Tom Lane. It is part of Red Hat AS 3.
> I have Postgresql 7.1.3-5 running on Red Hat AS 2.1.
> I have a simple view from which I select on both systems. The 7.3.6-7
> version requires 18+ seconds to do a select from a particular view.
> The 7.1.3-5 version requires 3+ seconds to select from the same view.

Have you run ANALYZE recently?

If so, take a look at the query plans produced by 7.1 and 7.3 (Using
EXPLAIN and EXPLAIN ANALYZE). Likely the planner is making an incorrect
decision -- EXPLAIN should help you figure out why. You can also post
the EXPLAIN / EXPLAIN ANALYZE output to the list and someone can give
you some advice. For more info:

http://www.postgresql.org/docs/7.4/static/performance-tips.html#USING-EXPLAIN

-Neil