I came across this performance study today, which comes to this conclusion: "If the graphs above are anything to go by, Java seems to be faster than C in most cases. The most significant of these, is the inlining optimizations that the HotSpot VM seems to employ. In some situations, the ServerVM is up to 2.4x the speed of GCC. "

But there's more, it links to another Performance Case Study, which states: "Remarkably, we were able to get better performance from our engine than one using similar algorithms written in C. "

That reminds me about another study, this one regarding designing high performance servers, it comes to this conclusion "We have built a number of applications to demonstrate the SEDA framework. Haboob is a a high-performance Web server including support for both static and dynamic pages that outperforms both Apache and Flash (which are implemented in C) on a SPECWeb99-like benchmark"