導讀:大多數網站的性能瓶頸不在PHP服務器上,因為它可以簡單地通過橫向增加服務器或CPU核數來輕松應對(對於各種雲主機,增加VPS或CPU核數就更方便了,直接以備份鏡像增加VPS,連操作系統、環境都不用安裝配置),而是在於MySQL數據庫。如果用 NoSQL 數據庫,也許需要十次查詢,才能處理完同樣地業務邏輯。此時PHP多線程的作用非常明顯,它可以同時執行NoSQL查詢大大的提升效率。
PHP 5.3 以上版本,使用pthreads PHP擴展,可以使PHP真正地支持多線程。多線程在處理重復性的循環任務,能夠大大縮短程序執行時間。
PHP擴展下載:https://github.com/krakjoe/pthreads
PHP手冊文檔:http://php.net/manual/zh/book.pthreads.php
1、擴展的編譯安裝(Linux),編輯參數 --enable-maintainer-zts 是必選項:
添加:
2、給出一段PHP多線程、與For循環,抓取百度搜索頁面的PHP代碼示例:
<?php class test_thread_run extends Thread { public $url; public $data; public function __construct($url) { $this->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 < 100; $i++) { $urls_array[] = array("name" => "baidu", "url" => "http://www.baidu.com/s?wd=".mt_rand(10000,20000)); } $t = microtime(true); $result = model_thread_result_get($urls_array); $e = microtime(true); echo "多線程:".($e-$t)."\n"; $t = microtime(true); foreach ($urls_array as $key => $value) { $result_new[$key] = model_http_curl_get($value["url"]); } $e = microtime(true); echo "For循環:".($e-$t)."\n"; ?>