Really? I haven't heard of that. In my experience, most of the alternative compiled JVM languages, i.e. Scala, Clojure, Mirah, and JRuby, seem to run fairly c

Really? I haven't heard of that. In my experience, most of the alternative compiled JVM languages, i.e. Scala, Clojure, Mirah, and JRuby, seem to run fairly comparable to each other once they have started. The biggest differentiator between them with respect to performance seems to be in the way of start time and heap overhead ranging from none (Mirah) to substantial (JRuby).