Benchmark to create an array on Ruby

array_benchmakr.rb

require "rubygems"
require "benchmark"


def run
  text = 'HEADER'
  n = 30
  n_times = 1_000_000
  base = [text]
  range = (1..30)
  header = ['REC_TYPE']

  Benchmark.bm(16) do |x|
    x.report("Array.new") { n_times.times { header + Array.new(n, text) } }
    x.report("[] * n") { n_times.times { header + base * n } }
    x.report("map") { n_times.times { header + range.map { text } } }
  end
  nil
end

run

puts "type 'run' to execute the benchmark"

__END__
                       user     system      total        real
Array.new          0.262522   0.094536   0.357058 (  0.379042)
[] * n             0.300455   0.049564   0.350019 (  0.356919)
map                1.564741   0.047170   1.611911 (  1.612839)