How to profile JRuby code?

Question

I'd like to profile my JRuby app. For MRI I always use ruby-prof, but I don't think this works on JRuby. I don't want to use a Java-profiler, because it won't give me the ruby line numbers.

Is there a jruby-prof?

Answer 1

JRuby 1.5.5 includes a decent --profile command line flag.

Use it like this:

jruby --profile -S <script> <args>