These benchmarks don't seem to take HotSpot compilation into account, which means some of those numbers are for interpreted Java bytecode and some of those numbers are for native code and you don't know which are which.

The behavior of the DBs as far as resource consumption is interesting, but the numbers are meaningless.

Further reading:

http://www.ibm.com/developerworks/java/library/j-jtp12214/

http://www.ibm.com/developerworks/java/library/j-jtp02225.ht...