For load testing your application to gather real data, consider the HttpClient package. For internal monitoring of response times and the time consumed by various parts of your application, consider the JAmon toolkit. Without real measurements and measuring technology in hand it doesn't make any sense to fiddle with settings. Bill
I admit my question was a little to general (sorry). The reason for this was that I do not know anything about how to check performance, and neither how to imrpve it. Thanks to both for informing me about measuring the current performance before starting any changes. Also thanks for the links, I will download those applications and see what I can do with them.
and next time I will try asking more specific questions (sorry for that again)