Profiling

Non-discriminatory profiling for your MRI Ruby code. This gem is a small wrapper around the ruby-prof gem, which is its only dependency. It lets you do simple but powerful profiling of your friend's bad code.

Installation

Add this line to your application's Gemfile:

gem 'profiling', "~> 2.1"

And then execute:

$ bundle

Or install it yourself as:

$ gem install profiling

Getting Started

Profile slow code from your friend or colleague like this:

Profiler.run do
  # Slow code here...
end

# or

Profiler.run("some-label") do
  # Slow code here...
end

The next time you call the code it will be profiled and three files will be written into a directory profiling, and in the second example profiling/some-label.

Files Generated

File	Description
graph.html	Drill down into the call tree to see where the time is spent
stack.html	See the profiled code as a nested stack
flat.txt	List of all functions called, the time spent in each and the number of calls made to that function

Configuration

Profiler.config = {
  dir: 'profiling', # Directory the files will be created in (default is 'profiling')
  exclude_gems: true, # Exclude ruby gems from the results (default is true)
  exclude_standard_lib: false # Exclude ruby standard library from results (default is false)
}

Rails Initializer

This initializer is recommended if you're planning to profile in Rails:

# config/initializer/profiling.rb
Profiler.config = {
  dir: Rails.root.join('tmp/profiling')
}

Conditional Profiling

Pass an argument if: to enable or disable profiling at run time:

Profiler.run(if: user.is_admin?) do
  # Slow code here...
end

Preserving artefacts

Every time code is profiled the previous files will be overwritten unless the label is dynamic. To keep old files, add the current time in the label so new files are generated with each run:

Profiler.run("my-label-#{Time.now.to_i}") do
  # Slow code here...
end

Organizing artefacts

Labels translate to directories, so use / in your labels to group artefacts together:

Profiler.run("post/create") do
  # Slow code here...
end

Profiler.run("post/update") do
  # Slow code here...
end

Contributing

Bug reports and pull requests are welcome.

To run the test suite:

bundle exec rspec

License

The gem is available as open source under the terms of the MIT License.