calling ruby method defined via define_method is 50% slower than via class_eval

def_benchmark.rb

# define benchmark from:
#http://www.mathewabonyi.com/articles/2007/01/11/surprise-10min-benchmark-eval-class_eval-instance_eval-define_method-bind#trackbacks
# but we're interested in the speed of calling the method not only defining it

# results with ruby 1.9.2-p180 on mbp i7

require 'benchmark'

class A; def meth1; true; end; end

# defining using eval/class/instance
str = "def meth2; true; end"
a_binding = A.send(:binding)

# proc for class/instance
proc1 = Proc.new { def meth2; true; end }

# proc for define_method
$proc2 = Proc.new { true }

# unbound method for bind
um = A.instance_method(:meth1)

# number of iterations
n = 300000 # * 600

Benchmark.bm(22) do |x|

  x.report('instance_eval/str') do
    for i in 1..n; A.instance_eval(str); end
  end

  x.report('class_eval/str') do
    for i in 1..n; A.class_eval(str); end
  end

  x.report('eval/str') do
    for i in 1..n; eval(str, a_binding); end
  end

  x.report('define_method/class') do
    for i in 1..n; class A; define_method(:meth2, &$proc2); end; end
  end

  x.report('define_method/send') do
    for i in 1..n; A.send(:define_method, :meth2, &$proc2); end
  end

  x.report('def/unbind/bind') do
    for i in 1..n
      class A; def meth2; true; end; end
      A.instance_method(:meth2).bind(A.new)
    end
  end

  x.report('instance_eval/proc') do
    for i in 1..n; A.instance_eval(&proc1); end
  end

  x.report('class_eval/proc') do
    for i in 1..n; A.class_eval(&proc1); end
  end

  x.report('def') do
    for i in 1..n; class A; def meth2; true; end; end; end
  end

  x.report('method/bind') do
    for i in 1..n; um.bind(A.new); end
  end

end
#                             user     system      total        real
# instance_eval/str       5.720000   0.030000   5.750000 (  5.807193)
# class_eval/str          5.800000   0.030000   5.830000 (  5.893954)
# eval/str                5.780000   0.030000   5.810000 (  5.860869)
# define_method/class     0.980000   0.010000   0.990000 (  0.990898)
# define_method/send      0.950000   0.030000   0.980000 (  0.979376)
# def/unbind/bind         1.340000   0.020000   1.360000 (  1.378884)
# instance_eval/proc      1.040000   0.010000   1.050000 (  1.100660)
# class_eval/proc         0.910000   0.010000   0.920000 (  0.919074)
# def                     0.950000   0.010000   0.960000 (  0.959918)
# method/bind             0.190000   0.000000   0.190000 (  0.198555)

puts "Calling defined method:"

class B; def meth1; true; end; end

# defining using eval/class/instance
str = "def meth2; true; end"
str3 = "def meth3; true; end"
B_binding = B.send(:binding)

# proc for class/instance
proc1 = Proc.new { def meth7; true; end }

# proc for define_method
$proc2 = Proc.new { true }

# unbound method for bind
um = B.instance_method(:meth1)

# number of iterations
n = 30000000 # * 600

Benchmark.bm(22) do |x|

  x.report('instance_eval/str') do
    B.instance_eval(str)
    for i in 1..n; B.meth2; end
  end

  x.report('class_eval/str') do
    B.class_eval(str)
    b = B.new
    for i in 1..n; b.meth2; end
  end

  # x.report('eval/str') do
  #   eval(str3, B_binding);
  #   b = B.new
  #   for i in 1..n;  b.meth3; end
  # end

  x.report('define_method/class') do
    class B; define_method(:meth4, &$proc2); end
    b = B.new
    for i in 1..n; b.meth4; end
  end

  x.report('define_method/send') do
    B.send(:define_method, :meth5, &$proc2); 
    b = B.new
    for i in 1..n; b.meth5; end
  end

  x.report('def/unbind/bind') do
    class B; def meth6; true; end; end
    B.instance_method(:meth6).bind(B.new)
    b = B.new
    for i in 1..n; b.meth6; end
  end

  x.report('instance_eval/proc') do
    B.instance_eval(&proc1); 
    for i in 1..n; B.meth7; end
  end

  x.report('class_eval/proc') do
    B.class_eval(&proc1); 
    b = B.new
    for i in 1..n; b.meth7; end
  end

  x.report('def') do
    class B; def meth8; true; end; end; 
    b = B.new
    for i in 1..n; b.meth8; end
  end

  # x.report('method/bind') do
  #   um.bind(A.new); 
  #   for i in 1..n; end
  # end

  # Calling defined method:
  #                             user     system      total        real
  # instance_eval/str       3.790000   0.010000   3.800000 (  3.832410)
  # class_eval/str          3.780000   0.020000   3.800000 (  3.816410)
  # define_method/class     5.990000   0.020000   6.010000 (  6.046599)
  # define_method/send      6.090000   0.030000   6.120000 (  6.156742)
  # def/unbind/bind         3.830000   0.020000   3.850000 (  3.889191)
  # instance_eval/proc      3.760000   0.010000   3.770000 (  3.786376)
  # class_eval/proc         3.840000   0.020000   3.860000 (  3.885466)
  # def                     4.410000   0.020000   4.430000 (  4.654724)

end