ContainerAwareEventDispatcher benchmark

<?php

use Symfony\Component\DependencyInjection\ContainerBuilder;
use Symfony\Component\DependencyInjection\Definition;
use Symfony\Component\EventDispatcher\ContainerAwareEventDispatcher;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\HttpFoundation\Request;

$autoloader = require_once __DIR__ . '/vendor/autoload.php';

$n_listeners = 1024;
$n_invocations = 10;

class Sub implements EventSubscriberInterface {

  public function onEvent() {
  }
  
  public static function getSubscribedEvents() {
    return array(
      'test.event' => array('onEvent', mt_rand(-1000, 1000)),
    );
  }
}

$t = array();

// Add definitions.
$t[] = microtime(TRUE);
$container = new ContainerBuilder();
for ($i = 0; $i < $n_listeners; $i++) {
  $c = new Sub();
  $container->setDefinition('subscriber_' . $i, new Definition('Sub'));
}

// Add subscribers.
$t[] = microtime(TRUE);
$event_dispatcher = new ContainerAwareEventDispatcher($container);
for ($i = 0; $i < $n_listeners; $i++) {
  $event_dispatcher->addSubscriberService('subscriber_' . $i, 'Sub');
}

// Prepare listeners.
$t[] = microtime(TRUE);
$event_dispatcher->getListeners('test.event');

// First call to dispatch.
$t[] = microtime(TRUE);
$event_dispatcher->dispatch('test.event');

// Subsequent calls to dispatch.
$t[] = microtime(TRUE);
for ($i = 0; $i < $n_invocations; $i++) {
  $event_dispatcher->dispatch('test.event');
}
$t[] = microtime(TRUE);

$dt = array();
for ($i = 1; $i < count($t); $i++) {
  $dt[] = $t[$i]-$t[$i-1];
}

error_log(implode(',', array_merge(array($n_listeners, $n_invocations), $dt)));