I agree that looking at just CPU is not a good guide. IO is usually the issue before cpu. If it was bad code the cpu might go 100% before the IO. But bus, memory etc all play a part. Did you switch to Postgres? Not sure if Derby is the best for load testing. I know with postgres each time a request is used it will use a new thread and can make use of multiple CPU. I am not sure if the JVM uses multiple core, but I imagine it has some form of using multiple threads.
Any how I appreciate your sharing you found 20 concurrent users seems to be a max. Not 100% sure, but I know I had to support 250 at my last job, but I used many techniques. For one I had three web servers. My Database server was very high end with fiber SAN. I used different app servers for different parts of my app. I was using liferay as my portal engine, and I even had a separate server or some of our larger clients, while smaller clients used a shared instance. I guess my point is there are many ways to get an application to handle the load. ----- Joel Fradkin -- View this message in context: http://ofbiz.135035.n4.nabble.com/Low-utilization-of-OFBiz-on-multi-core-servers-tp4653440p4653445.html Sent from the OFBiz - User mailing list archive at Nabble.com.
