Fast Ruby profiler

 ruby-prof is a fast code profiler for Ruby. It is a C extension and
 therefore is many times faster than the standard Ruby profiler. It
 supports both flat and graph profiles. For each method, graph profiles
 show how long the method ran, which methods called it and which
 methods it called. RubyProf generate both text and html and can output
 it to standard out or to a file.