Fabio,
> I'll have to get back to you on that, but I'm 90% sure its the default out
> of the box.
Raise it, a lot. Perhaps to 30,000 or 50,000. VACUUM VERBOSE ANALYZE
should show you how many data pages are being reclaimed between vacuums.
Because of your very high rate of updates and deletes, you need to hold a lot
of data pages open.
You would also benefit a great deal by upgrading to 7.4. 7.3 will require
you to to REINDEXes several times a day with your current setup; 7.4 will
not.
--
-Josh Berkus
Aglio Database Solutions
San Francisco
