Profile

Profile provides a way to Profile your Ruby application.

Profiling your program is a way of determining which methods are called and how long each method takes to complete. This way you can detect which methods are possible bottlenecks.

Profiling your program will slow down your execution time considerably, so activate it only when you need it. Don't confuse benchmarking with profiling.

Add this line to your application's Gemfile:

gem 'profile'

And then execute:

$ bundle

Or install it yourself as:

$ gem install profile

There are two ways to activate Profiling:

Run your Ruby script with -rprofile:

$ ruby -rprofile example.rb

If you're profiling an executable in your $PATH you can use ruby -S:

$ ruby -rprofile -S some_executable

Just require 'profile':

require 'profile'

def slow_method
  5000.times do
    9999999999999999*999999999
  end
end

def fast_method
  5000.times do
    9999999999999999+999999999
  end
end

slow_method
fast_method

The output in both cases is a report when the execution is over:

$ ruby -rprofile example.rb

 %   cumulative   self              self     total
time   seconds   seconds    calls  ms/call  ms/call  name
68.42     0.13      0.13        2    65.00    95.00  Integer#times
15.79     0.16      0.03     5000     0.01     0.01  Fixnum#*
15.79     0.19      0.03     5000     0.01     0.01  Fixnum#+
 0.00     0.19      0.00        2     0.00     0.00  IO#set_encoding
 0.00     0.19      0.00        1     0.00   100.00  Object#slow_method
 0.00     0.19      0.00        2     0.00     0.00  Module#method_added
 0.00     0.19      0.00        1     0.00    90.00  Object#fast_method
 0.00     0.19      0.00        1     0.00   190.00  #toplevel

After checking out the repo, run bin/setup to install dependencies. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Bug reports and pull requests are welcome on GitHub at https://github.com/ruby/profile.