model_benchmark.rb

require 'benchmark'

class MethodMissing
  attr_reader :attributes

  def initialize(attributes)
    @attributes = attributes
  end

  def method_missing(prop, *args, &block)
    return super unless @attributes.include?(prop)
    @attributes[prop]
  end
end

class MemoizedMethodMissing
  attr_reader :attributes

  def initialize(attributes)
    @attributes = attributes
  end

  def method_missing(prop, *args, &block)
    return super unless @attributes.include?(prop)
    define_singleton_method(prop) { @attributes[prop] }
    @attributes[prop]
  end
end

class DefineMethod
  attr_reader :attributes

  def initialize(attributes)
    @attributes = attributes
  end

  [:one, :two].each { |m| define_method(m) { @attributes[m] } }
end

Benchmark.bm do |x|
  mm = MethodMissing.new(one: 1, two: '2')
  mmm = MemoizedMethodMissing.new(one: 1, two: '2')
  dm = DefineMethod.new(one: 1, two: '2')

  x.report do
    500_000.times { mm.one; mm.two }
  end

  x.report do
    500_000.times { mmm.one; mmm.two }
  end

  x.report do
    500_000.times { dm.one; dm.two }
  end
end

# user     system      total        real
# 0.200000   0.000000   0.200000 (  0.208867)
# 0.110000   0.000000   0.110000 (  0.114226)
# 0.100000   0.000000   0.100000 (  0.115317)