clock.rb

# frozen_string_literal: true

require 'bundler/inline'

gemfile do
  source 'https://rubygems.org'
  gem 'benchmark-ips'
end

require 'benchmark/ips'

deadline = Process.clock_gettime(Process::CLOCK_MONOTONIC) + 20

i = 1
Benchmark.ips do |x|
  x.report("gettime") do
    Process.clock_gettime(Process::CLOCK_MONOTONIC) > deadline
  end

  x.report("modulo deadcode") do
    next unless (i % 100) == 0
    Process.clock_gettime(Process::CLOCK_MONOTONIC) > deadline # dead code
  end

  x.report("modulo match") do
    next unless (i % 100) == 1
    Process.clock_gettime(Process::CLOCK_MONOTONIC) > deadline # dead code
  end
  
  x.compare!(order: :baseline)
end

results.txt

$ ruby /tmp/clock.rb 
ruby 3.3.0 (2023-12-25 revision 5124f9ac75) [arm64-darwin23]
Warming up --------------------------------------
             gettime     1.380M i/100ms
     modulo deadcode     3.024M i/100ms
        modulo match     1.217M i/100ms
Calculating -------------------------------------
             gettime     13.799M (± 2.0%) i/s -     69.021M in   5.003809s
     modulo deadcode     30.462M (± 1.2%) i/s -    154.231M in   5.063728s
        modulo match     12.186M (± 1.2%) i/s -     62.066M in   5.093831s

Comparison:
             gettime: 13799327.6 i/s
     modulo deadcode: 30461955.9 i/s - 2.21x  faster
        modulo match: 12186249.3 i/s - 1.13x  slower


# ruby /app/clock.rb 
ruby 3.3.0 (2023-12-25 revision 5124f9ac75) [aarch64-linux]
Warming up --------------------------------------
             gettime   891.290k i/100ms
     modulo deadcode     1.605M i/100ms
        modulo match   768.553k i/100ms
Calculating -------------------------------------
             gettime      8.544M (± 4.7%) i/s -     42.782M in   5.020463s
     modulo deadcode     16.570M (± 2.9%) i/s -     83.447M in   5.040911s
        modulo match      7.798M (± 1.9%) i/s -     39.196M in   5.028306s

Comparison:
             gettime:  8544139.4 i/s
     modulo deadcode: 16569776.6 i/s - 1.94x  faster
        modulo match:  7798132.3 i/s - 1.10x  slower