[StefanKarpinski]

I have to whole-heartedly agree with Mike Pall and acqq's assessment that sampling profilers are vastly superior to instrumenting profilers when it comes to measuring true performance. Instrumenting is only reliable in languages that are so slow that instrumentation has no substantial effect on performance – instrumenting is fine, e.g. for Ruby or Matlab, but not fine for C or Fortran (or LuaJIT).

Also, Julia has a built-in sampling profiler (built by Tim Holy):

http://docs.julialang.org/en/latest/stdlib/profile/

Hard to say whether Julia qualifies as a "scripting language" though – that's a pretty meaningless term these days.