Rspec Benchmarking script. Put this file under `spec/supports/` and execute `BENCHMARK=1 rake spec`.

benchmark.rb

RSpec.configure do |config|
  next unless ENV['BENCHMARK'] == '1'
  benchmarks = []
  metadata_keys = %i[ file_path line_number described_class ]
  info_keys = %i[ type ] + metadata_keys + %i[ full_description ]
  log_file = Rails.root.join('log', 'rspec_benchmark.csv')
  config.before(:suite) do
    CSV.open(log_file, "wb") do |csv|
      csv << info_keys + %i[ utime stime cutime cstime real]
    end
  end
  config.around(:each) do |ex|
    example_info = metadata_keys.inject({}) { |memo, key| memo[key] = example.metadata[key]; memo }
    example_info[:type] = example.metadata[:file_path].match(/spec\/([^\/]*)/)[1]
    example_info[:full_description] = example.metadata.full_description
    bm = Benchmark.measure { ex.run }
    CSV.open(log_file, "a") do |csv|
      csv << ((info_keys).map { |key| example_info[key] }) + bm.to_a[1..-1]
    end
  end
end