what worked: performance improvements for geo-spatial searching on FreeBSD

The http://www.1-800-save-a-pet.com site is hosted with FreeBSD and
PostgreSQL and as a geo-spatial search as a central feature.

One thing that made a substantial performance improvement was switching
from the "geo_distance()" search in the earthdistance contrib, to use
the "cube" based geo-spatial calculations, also in available in contrib/
In our case, the slight loss of precision between the two methods didn't
matter.

The other things that made a noticeable performance improvement was
upgrading our servers from FreeBSD 4.x or 5.x (old, I know!) to FreeBSD
6.2 or later. We also upgrade these systems from PostgreSQL 8.1 to 8.2
at the same time. I assume the upgrade to 8.2 must be responsible at
least in part for the performance gains.

The result of these two rounds of updates is that our overall CPU
capacity in the cluster seems to be double or triple what it was before.

As the site grows we continue to be very happy with the performance,
features and stability of PostgreSQL.

Mark