导读:大多数网站的性能瓶颈不在PHP服务器上,因为它可以简单地通过横向增加服务器或CPU核数来轻松应对(对于各种云主机,增加VPS或CPU核数就更方便了,直接以备份镜像增加VPS,连操作系统、环境都不用安装配置),而是在于MySQL数据库。如果用 NoSQL 数据库,也许需要十次查询,才能处理完同样地业务逻辑。此时PHP多线程的作用非常明显,它可以同时执行NoSQL查询大大的提升效率。
PHP 5.3 以上版本,使用pthreads PHP扩展,可以使PHP真正地支持多线程。多线程在处理重复性的循环任务,能够大大缩短程序执行时间。
PHP扩展下载:https://github.com/krakjoe/pthreads
PHP手册文档:http://php.net/manual/zh/book.pthreads.php
1、扩展的编译安装(Linux),编辑参数 --enable-maintainer-zts 是必选项:
添加:
2、给出一段PHP多线程、与For循环,抓取百度搜索页面的PHP代码示例:
url = $url; } public function run() { if(($url = $this->url)) { $this->data = model_http_curl_get($url); } } } function model_thread_result_get($urls_array) { foreach ($urls_array as $key => $value) { $thread_array[$key] = new test_thread_run($value["url"]); $thread_array[$key]->start(); } foreach ($thread_array as $thread_array_key => $thread_array_value) { while($thread_array[$thread_array_key]->isRunning()) { usleep(10); } if($thread_array[$thread_array_key]->join()) { $variable_data[$thread_array_key] = $thread_array[$thread_array_key]->data; } } return $variable_data; } function model_http_curl_get($url,$userAgent="") { $userAgent = $userAgent ? $userAgent : 'Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2)'; $curl = curl_init(); curl_setopt($curl, CURLOPT_URL, $url); curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1); curl_setopt($curl, CURLOPT_TIMEOUT, 5); curl_setopt($curl, CURLOPT_USERAGENT, $userAgent); $result = curl_exec($curl); curl_close($curl); return $result; } for ($i=0; $i "baidu", "url" => "http://www.baidu.com/s?wd=".mt_rand(10000,20000)); } $t = microtime(true); $result = model_thread_result_get($urls_array); $e = microtime(true); echo "多线程:".($e-$t)."\n"; $t = microtime(true); foreach ($urls_array as $key => $value) { $result_new[$key] = model_http_curl_get($value["url"]); } $e = microtime(true); echo "For循环:".($e-$t)."\n"; ?>