Re: A tale of two similar databases

On Jan 17, 2006, at 18:22 , kishore(dot)sainath(at)gmail(dot)com wrote:

> I am using PostgreSQL 7.3.2 on a server running Red Hat Linux 9.0.

I'd highly recommend upgrading. The current release is 8.1.2. If you
can't upgrade to 8.1, at least upgrade to the latest point release of
7.3, which is 7.3.13. There are a number of security and critical bug
fixes.

> The strange thing is that D1 is extremely fast whereas D2 is
> relatively
> slow for any given query.
> (Thank God, it isnt the other way round :) )
>
> Eg,
> An extensive Statistics query returns in a matter of seconds on D1 but
> takes close to a minute on D2

How often do you run ANALYZE? I suspect your statistics are probably
off. Try running EXPLAIN ANALYZE on the queries and compare the
results. If you can provide more information such as relevant table
schema, the queries, and their EXPLAIN ANALYZE output, other list
members may be able to help you. You may also want to ask on the
pgsql-performance list.

Michael Glaesemann
grzm myrealbox com