lookup_bench.rb

class Aclass
  def some_method
  end
end

class Bclass < Aclass
end

class Cclass < Bclass
end

class Dclass < Cclass
end

module Amodule
  def some_method
  end
end

module Bmodule
end

module Cmodule
end

class DclassInheritedFromModules
  include Amodule
  include Bmodule
  include Cmodule
end

require "benchmark"

dmodule = DclassInheritedFromModules.new
dclass = Dclass.new

n = 100_000_000
Benchmark.bm do |x|
  x.report "class method lookup" do
    n.times { dclass.some_method }
  end

  x.report "module method lookup" do
    n.times { dmodule.some_method }
  end
end