Eventmachine and FiberIterator processing N requests per second with variable concurrency

gistfile1.rb

require 'rubygems'
require 'em-synchrony'
require 'em-synchrony/fiber_iterator'

EM.synchrony do
  values = (1..16).to_a

  {a: 2, b: 4, c: 8}.each do |label,concurrency|
    print "\n #{label}"
    EM::Synchrony::FiberIterator.new(values, concurrency).each do |val|
      print " #{val}"
      EM::Synchrony.sleep(1)
    end
  end
  EM.stop
end