I have been doing some perf testing for work. Using 3.2.2RC2. Testing MySQL SQLServer and Oracle comparing Entity EJB's and Apache OJB.
My original software config was a servlet using the resource locator then accessing the Entity EJB. I was getting horrible results; approx 4 seconds to return 128 rows of data!
Configuration 2; Servlet accessing a remote Session Bean which in turn used the same resource locator and then poked the Entity EJB; approx 200 Milliseconds!!!
Why such a HUGE increase in performance?
You might want to do some reading on the Session Facade Design Pattern.