vendor/rails/actionpack/lib/action_view/helpers/benchmark_helper.rb

   1 require 'benchmark'
   2
   3 module ActionView
   4   module Helpers
   5     # This helper offers a method to measure the execution time of a block
   6     # in a template.
   7     module BenchmarkHelper
   8       # Allows you to measure the execution time of a block
   9       # in a template and records the result to the log. Wrap this block around
  10       # expensive operations or possible bottlenecks to get a time reading
  11       # for the operation.  For example, let's say you thought your file
  12       # processing method was taking too long; you could wrap it in a benchmark block.
  13       #
  14       #  <% benchmark "Process data files" do %>
  15       #    <%= expensive_files_operation %>
  16       #  <% end %>
  17       #
  18       # That would add something like "Process data files (345.2ms)" to the log,
  19       # which you can then use to compare timings when optimizing your code.
  20       #
  21       # You may give an optional logger level as the second argument
  22       # (:debug, :info, :warn, :error); the default value is :info.
  23       def benchmark(message = "Benchmarking", level = :info)
  24         if controller.logger
  25           seconds = Benchmark.realtime { yield }
  26           controller.logger.send(level, "#{message} (#{'%.1f' % (seconds * 1000)}ms)")
  27         else
  28           yield
  29         end
  30       end
  31     end
  32   end
  33 end