Simple Ractor test based on Koichi's example at https://bugs.ruby-lang.org/issues/17497

gistfile1.txt

#!/usr/bin/env ruby

# Run in directory containing `compar.c`, e.g. from https://github.com/ruby/ruby/blob/master/compar.c.

require 'etc'

WORDS = Ractor.make_shareable File.readlines('/usr/share/dict/words').map(&:chomp).map(&:downcase).sort
TRY_COUNT = Etc.nprocessors

puts "Measuring first sequentially on main ractor and then with #{TRY_COUNT} ractors:\n\n"

def try
  File.readlines(__dir__ + '/compar.c').each{|line|
    line.split.map(&:downcase).select { |text|
      WORDS.include? text
    }
  }
end

Warning[:experimental] = false

require 'benchmark'

Benchmark.bm{|x|
  obs_1 = x.report{
    TRY_COUNT.times{try}
  }
  obs_n = x.report{
    TRY_COUNT.times.map{
      Ractor.new{ try }
    }.each(&:take)
  }
            
  puts "\n#{sprintf("%7.3f", obs_1.utime / obs_n.utime)}  User time difference factor"
  puts "#{sprintf("%7.3f",   obs_1.real  / obs_n.real) }  Real time difference factor"
}