Have tracing JIT compilers won? | Lambda the Ultimate. Interesting discussion in which Mike Pall (LUAJit), Brendan Eich (Mozilla JägerMonkey) also participate (and specifically LUAJit is currently the King of the Mountains in terms of performance). PyPy is also mentioned, though still at a much older stage - the new 1.4 already shows much better what is possible with PyPy.