Added an off heap hash map to the OpenHFT/HugeCollections library. It has a test which does put/get/remove 100 million entries at 14 million operations per second with a 64 MB young gen without a GC. (less than one byte of heap per entry)
An interesting performance tool for cloud based systems. A common problem with clouds and Java is a tools which can help you diagnose performance problems. This looks like a step in the right direction.