Time to add a new key/value pair (ms)

hash_size.rb

# Ruby -v: 2.3.4
# Chart: https://jsfiddle.net/81ef590x/116/

require 'benchmark'

def without_gc
  GC.start
  GC.disable
  yield
  GC.enable
end

170.times do |size|
  without_gc do
    hashes = []

    100000.times do
      hash = {}

      (1..size).each do
        hash[rand] = rand
      end

      hashes << hash
    end

    Benchmark.bm do |bench|
      bench.report("adding element number #{size+1}") do
        100000.times do |n|
          hashes[n][size] = rand
        end
      end
    end
  end
end