You should be able to find several of these in classes with obvious names (RubyObject, RubyArray, RubyException, etc) here https://github.com/jruby/jruby/tree/master/core/src/main/java/org/jruby
To understand more about JRuby internals, there are some good presentation slides here http://www.slideshare.net/calavera/jruby-hacking-guide http://www.slideshare.net/marakana/learn-about-jruby-internals-from-one-of-the-jruby-lead-developers-thomas-enebo http://prezi.com/tsuouxb3z4ln/jruby-hacking-guide/ A bit curios about the GC ones - JRuby just depends transparently on whichever JVM GC have been configured, so I don't think you can get any more information than the probes already provided by the JVM. http://docs.oracle.com/javase/7/docs/technotes/guides/vm/dtrace.html#Garbage_Collection_Probes Regards, Lars
