benchmark.rb

require 'benchmark'
require 'pp'

class App
  def initialize
    $realm_match = Regexp.new(ENV['CLOUDAPI_DISABLE_REALM_MATCH']) rescue false
    @@realm_match = Regexp.new(ENV['CLOUDAPI_DISABLE_REALM_MATCH']) rescue false
    @realm_match = Regexp.new(ENV['CLOUDAPI_DISABLE_REALM_MATCH']) rescue false
    $_match = nil
    @@_match = nil
  end

  def wolanin_match?(realm)
    ENV['CLOUDAPI_DISABLE_REALM_MATCH'] && /#{ENV['CLOUDAPI_DISABLE_REALM_MATCH']}/ =~ realm
  end

  # Actually, this raises when not set.
  #def smith_match?(realm)
  #  !!(Regexp.new(ENV['CLOUDAPI_DISABLE_REALM_MATCH']) =~ realm)
  #end

  def pratt_match?(realm)
    !ENV['CLOUDAPI_DISABLE_REALM_MATCH'].nil? && !!(Regexp.new(ENV['CLOUDAPI_DISABLE_REALM_MATCH']) =~ realm)
  end

  def const_match?(realm)
    CLOUDAPI_DISABLE_REALM_MATCH =~ realm
  end

  def const_bool_match?(realm)
    !!(CLOUDAPI_DISABLE_REALM_MATCH =~ realm)
  end

  def global_cache_match?(realm)
    if $_match.nil?
      $_match = Regexp.new(ENV['CLOUDAPI_DISABLE_REALM_MATCH']) rescue false
    end
    $_match =~ realm
  end

  def class_cache_match?(realm)
    if @@_match.nil?
      @@_match = Regexp.new(ENV['CLOUDAPI_DISABLE_REALM_MATCH']) rescue false
    end
    @@_match =~ realm
  end

  def instance_cache_match?(realm)
    if @_match.nil?
      @_match = Regexp.new(ENV['CLOUDAPI_DISABLE_REALM_MATCH']) rescue false
    end
    @_match =~ realm
  end

  def global_startup_match?(realm)
    $realm_match =~ realm
  end

  def class_startup_match?(realm)
    @@realm_match =~ realm
  end

  def instance_startup_match?(realm)
    @realm_match =~ realm
  end
end

def test(app, realm, match)
  methods = app.methods.grep(/match\?/)
  methods.each do |method_symbol|
    method = app.method(method_symbol)
    result = method.call(realm)
    if match
      puts "#{method_symbol} expected #{match} got #{result.inspect}" unless result
    else
      puts "#{method_symbol} expected #{match} got #{result.inspect}" if result
    end
  end
end

def benchmark(app, realm, iterations = 100000)
  Benchmark.bm(25) do |bm|

    bm.report('wolanin') do
      iterations.times do
        app.wolanin_match?(realm)
      end
    end

#    bm.report('smith') do
#      iterations.times do
#        app.smith_match?(realm)
#      end
#    end
  
    bm.report('pratt') do
      iterations.times do
        app.pratt_match?(realm)
      end
    end

    bm.report('const_match') do
      iterations.times do
        app.const_match?(realm)
      end
    end

    bm.report('const_bool_match') do
      iterations.times do
        app.const_bool_match?(realm)
      end
    end

    bm.report('global_cache_match') do
      iterations.times do
        app.global_cache_match?(realm)
      end
    end

    bm.report('class_cache_match') do
      iterations.times do
        app.class_cache_match?(realm)
      end
    end

    bm.report('instance_cache_match') do
      iterations.times do
        app.instance_cache_match?(realm)
      end
    end

    bm.report('global_startup_match') do
      iterations.times do
        app.global_startup_match?(realm)
      end
    end

    bm.report('class_startup_match') do
      iterations.times do
        app.class_startup_match?(realm)
      end
    end

    bm.report('instance_startup_match') do
      iterations.times do
        app.instance_startup_match?(realm)
      end
    end

  end
end

puts " --- ENV unset, no match"
app = App.new
CLOUDAPI_DISABLE_REALM_MATCH = Regexp.new(ENV['CLOUDAPI_DISABLE_REALM_MATCH']) rescue false
test(app, 'devcloud', false)
benchmark(app, 'devcloud')

puts
puts " --- ENV set, matches"
ENV['CLOUDAPI_DISABLE_REALM_MATCH'] = 'devcloud'
app = App.new
# Re-assignment generates a warning, don't care.
$VERBOSE = nil
CLOUDAPI_DISABLE_REALM_MATCH = Regexp.new(ENV['CLOUDAPI_DISABLE_REALM_MATCH']) rescue false
test(app, 'devcloud', true)
benchmark(app, 'devcloud')

puts
puts " --- ENV set, no match"
app = App.new
test(app, 'network', false)
benchmark(app, 'network')

|ruby-2.0.0-p353| $ ruby benchmark.rb 
 --- ENV unset, no match
                                user     system      total        real
wolanin                     0.210000   0.000000   0.210000 (  0.204374)
pratt                       0.220000   0.000000   0.220000 (  0.226874)
const_match                 0.090000   0.000000   0.090000 (  0.089160)
const_bool_match            0.110000   0.000000   0.110000 (  0.109304)
global_cache_match          0.140000   0.000000   0.140000 (  0.132800)
class_cache_match           0.210000   0.000000   0.210000 (  0.220921)
instance_cache_match        0.150000   0.000000   0.150000 (  0.141810)
global_startup_match        0.090000   0.000000   0.090000 (  0.090267)
class_startup_match         0.130000   0.000000   0.130000 (  0.130027)
instance_startup_match      0.090000   0.000000   0.090000 (  0.093800)

 --- ENV set, matches
                                user     system      total        real
wolanin                     4.530000   0.020000   4.550000 (  4.570830)
pratt                       4.220000   0.010000   4.230000 (  4.258453)
const_match                 0.600000   0.000000   0.600000 (  0.600909)
const_bool_match            0.700000   0.010000   0.710000 (  0.722437)
global_cache_match          0.710000   0.000000   0.710000 (  0.720152)
class_cache_match           0.830000   0.000000   0.830000 (  0.832805)
instance_cache_match        0.680000   0.010000   0.690000 (  0.686846)
global_startup_match        0.630000   0.000000   0.630000 (  0.630173)
class_startup_match         0.660000   0.000000   0.660000 (  0.670518)
instance_startup_match      0.590000   0.000000   0.590000 (  0.591996)

 --- ENV set, no match
                                user     system      total        real
wolanin                     4.530000   0.020000   4.550000 (  4.611864)
pratt                       3.730000   0.010000   3.740000 (  3.764850)
const_match                 0.290000   0.000000   0.290000 (  0.284955)
const_bool_match            0.300000   0.000000   0.300000 (  0.301784)
global_cache_match          0.330000   0.000000   0.330000 (  0.337714)
class_cache_match           0.410000   0.000000   0.410000 (  0.410488)
instance_cache_match        0.360000   0.000000   0.360000 (  0.360238)
global_startup_match        0.280000   0.000000   0.280000 (  0.291208)
class_startup_match         0.320000   0.000000   0.320000 (  0.328929)
instance_startup_match      0.290000   0.000000   0.290000 (  0.290356)