"bill.burke(a)jboss.com" wrote : Maybe it is classloading that is the culprit? Fast-jaxb has no binding time, but the first time you parse requires loading classes. Each JAXB annotated class = 1 Parser class in the model I created. Since JAXB already has had its classes loaded at bind time, this overhead isn't accounted for in the test. I doubt that would make a difference for this test since I think there are only 2 classes? It shouldn't take 0.8 seconds to do that. ;-) But it also wouldn't be a fair test if you excluded the extra classloading time from the numbers. We want to know which is faster in the real world. The overhead of the extra classes are an argument against the code generation in that case. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4257951#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...