Ruby ruby-prof
From wikinotes
A cross platform profiler for ruby.
dump to a file, then obtain reports like flamegraphs, call-trees, etc.
Documentation
official docs https://ruby-prof.github.io/
Example
1: Add 'ruby-prof' to Gemfile 2: bundle install# 3: write file: foo.rb def flat_printer(result) printer = RubyProf::FlatPrinter.new(result) File.open("out.prof", "w") do |fd| printer.print(fd, {}) end puts(File.read("out.prof")) puts("---------------------------") puts("RESULTS WRITTEN TO out.prof") puts("---------------------------") end def callstack_printer(result) printer = RubyProf::CallStackPrinter.new(result) Tempfile.create(["foo", ".html"]) do |fo| printer.print(fo) %x{open -a "Google Chrome.app" -W "#{fo.path}"} end end Rails.application.eager_load! result = RubyProf.profile do # ... your code to profile ... end flat_printer(result) callstack_printer(result)4: cat foo.rb | rails c 5: a colour-coded flamegraph!