00_php

$ php -v
PHP 5.5.14-2+deb.sury.org~precise+1 (cli) (built: Jul  2 2014 12:07:02)
Copyright (c) 1997-2014 The PHP Group
Zend Engine v2.5.0, Copyright (c) 1998-2014 Zend Technologies
    with Zend OPcache v7.0.4-dev, Copyright (c) 1999-2014, by Zend Technologies
    with Xdebug v2.2.5, Copyright (c) 2002-2014, by Derick Rethans

artax_multi.php

 <?php
// 
//real    0m2.103s
//user    0m0.160s
//sys     0m0.448s


 require_once __DIR__ . '/vendor/autoload.php';
 require_once __DIR__ . '/vendor/rdlowrey/after/lib/functions.php';

 $client = new Artax\Client;
 $arrayOfPromises = $client->requestMulti(iterator_to_array(requests_generator()));

 list($errors, $responses) = After\some($arrayOfPromises)->wait();

 foreach ($responses as $key => $response) {
     //printf(
     //    "%s | HTTP/%s %d %s\n",
     //    $key,
         //$response->getProtocol(),
         //$response->getStatus(),
         //$response->getReason()
     echo $response->getBody();
     //);
 }

 function requests_generator()
 {

     // IDの若いGitHubユーザー20人
     $loginIds = [
         'mojombo', 'defunkt', 'pjhyett', 'wycats', 'ezmobius',
         'ivey', 'evanphx', 'vanpelt', 'wayneeseguin', 'brynary',
         'kevinclark', 'technoweenie', 'macournoyer', 'takeo', 'Caged',
         'topfunky', 'anotherjesse', 'roland', 'lukas', 'fanvsfan',
     ];
     foreach ($loginIds as $loginId) {
         yield $loginId => 'https://github.com/'.$loginId.'.keys';
     }
 }

guzzle4.php

<?php
 // borrowed from http://d.hatena.ne.jp/hnw/20140824
 
// real    0m3.292s
// user    0m0.160s
// sys     0m0.384s

 
 use GuzzleHttp\Client;
 use GuzzleHttp\Event\CompleteEvent;

 require_once __DIR__.'/vendor/autoload.php';

 $client = new Client();
 $client->sendAll(requests_generator($client), [
         'parallel' => 4,
         'complete' => function (CompleteEvent $event) {
         //    echo 'Completed request to ' . $event->getRequest()->getUrl() . "\n";
             echo 'Response: ' . $event->getResponse()->getBody() . "\n\n";
         }
     ]);


 function requests_generator($client)
 {
     // IDの若いGitHubユーザー20人
     $loginIds = [
         'mojombo', 'defunkt', 'pjhyett', 'wycats', 'ezmobius',
         'ivey', 'evanphx', 'vanpelt', 'wayneeseguin', 'brynary',
         'kevinclark', 'technoweenie', 'macournoyer', 'takeo', 'Caged',
         'topfunky', 'anotherjesse', 'roland', 'lukas', 'fanvsfan',
     ];
     foreach ($loginIds as $loginId) {
         yield $client->createRequest('GET', 'https://github.com/'.$loginId.'.keys');
     }
 }