Benchmark of Set vs Ruby Hash vs Google Dense Hash vs Google Sparse Hash

benchmark.rb

#!/usr/bin/env ruby

require 'set'
require 'google_hash'
require 'benchmark'

set    = Set.new
hash   = Hash.new(0)
ghashd = GoogleHashDenseIntToInt.new
ghashs = GoogleHashSparseIntToInt.new

max = 200_000
n   = 10_000_000

Benchmark.bm() do |x|
  x.report("Set")                { n.times { set.add(rand(max)) } }
  x.report("Ruby Hash")          { n.times {    hash[rand(max)] = 1 } }
  x.report("Google Hash Dense")  { n.times {  ghashd[rand(max)] = 1 } }
  x.report("Google Hash Sparse") { n.times {  ghashs[rand(max)] = 1 } }
end

benchmark.txt

./benchmark.rb
       user     system      total        real
Set  6.490000   0.020000   6.510000 (  6.595643)
Ruby Hash  5.950000   0.030000   5.980000 (  6.066545)
Google Hash Dense  5.830000   0.010000   5.840000 (  5.904371)
Google Hash Sparse  9.490000   0.010000   9.500000 (  9.531793)