module Benchmark

Performance benchmarking library

Public Class Methods

ips() click to toggle source

require 'benchmark/ips'

Benchmark.ips do |x|
  # Configure the number of seconds used during
  # the warmup phase (default 2) and calculation phase (default 5)
  x.config(:time => 5, :warmup => 2)

  # These parameters can also be configured this way
  x.time = 5
  x.warmup = 2

  # Typical mode, runs the block as many times as it can
  x.report("addition") { 1 + 2 }

  # To reduce overhead, the number of iterations is passed in
  # and the block must run the code the specific number of times.
  # Used for when the workload is very small and any overhead
  # introduces incorrectable errors.
  x.report("addition2") do |times|
    i = 0
    while i < times
      1 + 2
      i += 1
    end
  end

  # To reduce overhead even more, grafts the code given into
  # the loop that performs the iterations internally to reduce
  # overhead. Typically not needed, use the |times| form instead.
  x.report("addition3", "1 + 2")

  # Really long labels should be formatted correctly
  x.report("addition-test-long-label") { 1 + 2 }

  # Compare the iterations per second of the various reports!
  x.compare!
end

This will generate the following report:

Calculating -------------------------------------
            addition    71.254k i/100ms
           addition2    68.658k i/100ms
           addition3    83.079k i/100ms
addition-test-long-label
                        70.129k i/100ms
-------------------------------------------------
            addition     4.955M (± 8.7%) i/s -     24.155M
           addition2    24.011M (± 9.5%) i/s -    114.246M
           addition3    23.958M (±10.1%) i/s -    115.064M
addition-test-long-label
                         5.014M (± 9.1%) i/s -     24.545M

Comparison:
           addition2: 24011974.8 i/s
           addition3: 23958619.8 i/s - 1.00x slower
addition-test-long-label:  5014756.0 i/s - 4.79x slower
            addition:  4955278.9 i/s - 4.85x slower