Postgres is slow

Dear All,

I am using Postgres 7.4 on Fedora 3.0. It is running with the default
configuration.

I have a Java code which is using the JDBC 3.0 implementation and the
connection pooling implementation of the Postgres.

I have some tests running against this implementation. I do inserts of
100,000 records. The primary key of this table is a byte array.

The time required for lookup on this 100,000 records keeps increasing
with subsequent tests even though I am not inserting/updating any
recors.

I also noticed that with every test the size of "base" directory which
is there in my DB keeps increasing. I don't think this is a log
directory, then why should its size increase with just "select"
queries? What is it logging?

Can somebody help on this? I think its some misconfiguration on my part?

-Prajakt