Ruby benchmark: 10 million Float to Integer

bm-ftoi.rb

require 'benchmark'
require 'carray'
require 'etc'
Ractor.new {}  # show "warning: Ractor is experimental..."
puts "Making an Array of Floats..."
array = 10_000_000.times.map{500 * rand}
array1, array2, array3 = nil
nproc = Etc.nprocessors
Benchmark.bmbm do |x|
  x.report("Float#to_i") {array1 = array.map &:to_i}
  x.report("CArray") {array2 = CA_DOUBLE(array1).int.to_a}
  x.report("Ractor") do
    size = array.size.quo(nproc).ceil  # size / nproc rounded up
    array3 = array.each_slice(size).map do |part|
      Ractor.new(part) {|part| Ractor.yield part.map &:to_i}
    end.flat_map &:take
  end
end
puts "-- Used #{nproc} Ractors."
array1 == array2 or fail "CArray gave wrong answer"
array1 == array3 or fail "Ractor gave wrong answer"