By default, postgresql-server is tuned to run on a minimal system. There is a python script called pgtune which can be used to set reasonable defaults for PostgreSQL for a variety of types of applications (web, desktop, oltp, etc.)

Josh Berkus has suggested using pgtune (http://pgfoundry.org/projects/pgtune/) to determine what settings to use.

It would be ideal to integrate pgtune into Funtoo's postgresql-server, possibly with the 1.0 profile to allow postgresql to auto-tune itself for the intended use of the system.

Note that Josh Berkus has said he needs to tweak the script a bit first to provide better tuning for the most recent versions of PostgreSQL.