test.local.extend.rb

# Shows the difference in doing crazy stuff like extending an instance on a say... busy loop or lots of requests.
#
# [16:38][wmaldonado@wmaldonado0:]$ ruby test.local.extend.rb 
#                  user     system      total        real
#  extend instance 23.150000   0.430000  23.580000 ( 23.777088)
#  create a class  2.390000   0.810000   3.200000 (  3.209350)
#

require 'benchmark'

module SomethingToExtendStringWith

  [:one, :two, :three, :four, :five, :six].each do |mname|
    define_method("something_#{mname}") do

    end
  end

end

class SomethingClass
  def initialize(what)
     @what = what
  end

 include SomethingToExtendStringWith 
end

n = 1000000

Benchmark.bm do |bm|

  bm.report("extend instance"){
      n.times do
        str = ""
        str.extend SomethingToExtendStringWith
      end
  }
  bm.report("create a class") {
      n.times do
        str = ""
        parser = SomethingClass.new(str)
      end
  }
end