Benchmark callable vs proc as event handlers

benchmark.rb

class EventHandler
  def call event
  end
end

class Eventable
  def initialize
    @events = Hash.new { |h, k| h[k] = [] }
  end

  def on event_name, handler=nil, &block
    @events[event_name] << (handler || block)
  end

  def trigger event_name, event
    @events[event_name].each { |handler| handler.call event }
  end
end

callables = Eventable.new
procs = Eventable.new
mix = Eventable.new

2.times { callables.on(:foo, EventHandler.new) }
2.times { procs.on(:foo) {} }
mix.on(:foo, EventHandler.new)
mix.on(:foo) {}

Benchmark.ips do |x|
  x.report('callables') { callables.trigger :foo, 1 }
  x.report('procs') { procs.trigger :foo, 1 }
  x.report('mix') { mix.trigger :foo, 1 }

  x.compare!
end

results-mri-2.5.1

Comparison:
           callables:  3788280.0 i/s
               procs:  2606729.7 i/s - 1.45x  slower
                 mix:  2446583.1 i/s - 1.55x  slower