Simple Benchmarking Ruby Script

gistfile1.rb

#! /usr/bin/env ruby
require 'benchmark'

#
#  Benchmarking cmd-line tool
#
#
# $ bench_it.rb  "x = 5; 100.times { x * 5 }" "(1..1000).to_a.inject(:+)" --times=500
#
# EXAMPLE OUTPUT
#
# ==============
# [Trial 1], 500 time(s)
# 	"x = 5; 100.times { x * 5 }":
# ==============
#   0.020000   0.000000   0.020000 (  0.023091)
#
#
#
# ==============
# [Trial 2], 500 time(s)
# 	"(1..1000).to_a.inject(:+)":
# ==============
#   0.100000   0.000000   0.100000 (  0.101163)
#
def p_howto
  puts <<-EOL
  Accepts arbitrary number of blocks to benchmark:
  $ bench_it.rb  "x = 5; 100.times { x * 5 }" "(1..1000).to_a.inject(:+)"

  use times option to run additional amount: "--times=[n]"
  $ bench_it.rb  "x = 5; 100.times { x * 5 }" "(1..1000).to_a.inject(:+)" --times=500
  EOL
  exit
end


#
# NOTE:  This is a geto option parser.  Don't tell
# the creator of Trollop (http://trollop.rubyforge.org/),
# he will be a lil angry
#
def many!
  @many ||= begin
    if opt = ARGV.grep(/--times=/).first
       _, many = opt.split(/=/, 2).map &:to_i
      ARGV.delete opt
    end
    many || 1
  end
end

alias :many :many!

def p_header(code, trial)
  str =  %{\n==============\n[Trial #{trial}]}
  str << %{, #{many} time(s)\n\t"#{code}":}
  str << %{\n==============\n\n}
  puts str
end

def get_lambda(code)
  if many > 1
    lambda { many.times { eval(code) } }
  else
    lambda { eval(code) }
  end
end

def run!
  many!

  if ARGV.empty?
    p_howto
    exit
  end

  ARGV.each_with_index do |arg, i|
    p_header(arg, i + 1)

    lamb = get_lambda(arg)
    puts Benchmark.measure { lamb.call }
  end
end

run! if $0 == __FILE__