Another important performance issue is related to Java's handling about generic type erasure and auto boxing. This is one of the biggest design issue comparing with C#'s handling. So manipulating bytes is a pain. And there is even no unsigned byte. Benchmark does not represent real world use case. I don't feel Java is much faster than Python or Ruby. But there is too much boilerplate code comparing with C#. The pure Java language is clean. But with Spring framework and various Apache common, endless different logging framework, it makes the language such a hassle to deal with. Just my 2 cents.