bench.rb

require "rubygems"
require "rbench"

class A
  def initialize(hash={})
    hash.each do |key, value|
      instance_variable_set(:"@#{key}", value)
    end
  end
end

class B < A
  def initialize(hash={})
    super(hash)
  end
end

class C < A
  def initialize(hash={})
    @a = hash[:a]
    @b = hash[:b]
    @c = hash[:c]
  end
end

def base
  A.new({:a => 1, :b => 2, :c => 3})
end

def with_super
  B.new({:a => 1, :b => 2, :c => 3})
end

def without_super
  C.new({:a => 1, :b => 2, :c => 3})
end

RBench.run(100_000) do
  column :one, :title => 'Base class'
  column :two, :title => 'Child class with super'
  column :three, :title => 'Child class without super'

  report "Which is fastest?" do
    one{base}
    two{with_super}
    three{without_super}
  end
end

__END__
                          Base class | Child class with super | Child class without super |
-------------------------------------------------------------------------------------------
Which is fastest?              0.912 |                  0.955 |                     0.392 |