[rules-users] multiprocessor and performance

Hi all, I've got a fairly simple web application with DRools 4.0.3 deployed on a Tomcat 5.5, where I'm running a stress test of about 100 users doing fact changes every half a second. There are about 20 rules and about 20 facts. Each action loads and compiles the rule base, creates a new working memory and creates the facts inside it. I know it's not efficient (rules should be loaded only once in the application, working memory should be created only once in the session) but that's not my question. This is a 4-way machine. 1. if I don't load and use drools, the web application uses all 4 processors 2. if drools does the above mentioned work, only ONE processor is used, at about 100% CPU. Does it make sense that way? Do I have to set anything so the other processors are used as well? Otherwise, I'd have a general performance question: is it more efficient to empty the WM (one fact at a time) each time many facts need to be reloaded, or just drop it and create it again? I'm talking about some 200 facts, and a few hundred rules. Thanks a lot, M