It's not true that the VM changes focus mostly on the GCs. There have been significant changes to startup time and low-overhead profiling. And there are constan

It's not true that the VM changes focus mostly on the GCs. There have been significant changes to startup time and low-overhead profiling. And there are constant improvements in the JIT compilers. Project Loom's lightweight concurrency also involves big VM changes, but without any bytecode changes. Reified runtime generics for reference types is a bad idea; it destroys language interop for very little gain. Value types and specialized generics for value types, on the other hand, are in the works. You can download and play with them here: http://jdk.java.net/valhalla/ http://jdk.java.net/valhalla/