ruby_benchmark.rb

require 'benchmark'
require 'test/unit'
include Test::Unit::Assertions


# Create values
# data: [{id, quantity }, {location_id, quantity }]

def test_values
    data = []
    location_count = 1_000
    max_quantity = 10_000
    data_count = 1_000

    data_count.times do
        data << {id: rand(location_count), quantity: rand(max_quantity)}
    end

    data
end

def count_one_line(data)
  data.each_with_object({}) do |item, count_hash|
    count_hash[item[:id]] = (count_hash[item[:id]] || 0) + item[:quantity]
  end
end

def count_two_lines(data)
  data.each_with_object({}) do |item, count_hash|
    count_hash[item[:id]] = count_hash[item[:id]] || 0
    count_hash[item[:id]] += item[:quantity]
  end
end

N = 10_000
TEST_VALUES = test_values
assert_equal count_one_line(TEST_VALUES), count_two_lines(TEST_VALUES)


Benchmark.bm do |benchmark|
  benchmark.report("count_one_line") do
    N.times do
        count_one_line(TEST_VALUES)
    end
  end

  benchmark.report("count_two_lines") do
    N.times do
        count_two_lines(TEST_VALUES)
    end
  end
end

=begin
$ ruby benchmark-simple.rb
       user     system      total        real
count_one_line  3.074869   0.042140   3.117009 (  3.120487)
count_two_lines  4.255742   0.030403   4.286145 (  4.290792)
=end