measurerails2.rb

require "json"
require "benchmark"

class Measure
  def self.run(&block)
    no_gc = (ARGV[0] == "--no-gc")
    if no_gc
      GC.disable
    else
    # collect memory allocated during library loading # and our own code before the measurement
    GC.start
    end
    memory_before = `ps -o rss= -p #{Process.pid}`.to_i/1024
    time = Benchmark.realtime do
      yield
    end
    GC.start unless no_gc
    memory_after = `ps -o rss= -p #{Process.pid}`.to_i/1024

    puts({
        RUBY_VERSION => {
          :gc => no_gc ? 'disabled' : 'enabled',
          :time => time.round(2),
          :memory => "%dM" % (memory_after - memory_before)
          }
        }.to_json)
  end
end