macruby_parallel_map_benchmarking

require 'benchmark'
require 'matrix'

class Array
  def parallel_map(&block)
    result = []
    # Creating a group to synchronize block execution.
    group = Dispatch::Group.new
    # We will access the `result` array from within this serial queue,
    # as without a GIL we cannot assume array access to be thread-safe.
    result_queue = Dispatch::Queue.new('access-queue.#{result.object_id}')
    0.upto(size) do |idx|
      # Dispatch a task to the default concurrent queue.
      Dispatch::Queue.concurrent.async(group) do
        temp = block[self[idx]]
        puts temps
        result_queue.async(group) { result[idx] = temp }
      end
    end
    # Wait for all the blocks to finish.
    group.wait
    result
  end
end

FIB_MATRIX = Matrix[[1,1],[1,0]]
def fib(n)
  (FIB_MATRIX**(n-1))[0,0]
end

N = 100000
M = 32
ARR = (0..M).to_a
T = 50

Benchmark.bm do |b|
  b.report(">> ") do
    T.times { ARR.map{ fib N } }
  end
  b.report("++ ") do
    T.times { ARR.parallel_map{ fib N } }
  end
end