在我們平時的程序中難免出現同時訪問幾個接口的情況，平時我們用curl進行訪問的時候，一般都是單個、順序訪問，假如有3個接口，每個接口耗時500毫秒那么我們三個接口就要花費1500毫秒了，這個問題太頭疼了嚴重影響了頁面訪問速度，有沒有可能并發訪問來提高速度呢？今天就簡單的說一下，利用curl并發來提高頁面訪問速度， 希望大家多指導。

<?phpfunction curl_fetch($url, $timeout=3){ $ch = curl_init(); curl_setopt($ch, CURLOPT_URL, $url); curl_setopt($ch, CURLOPT_TIMEOUT, $timeout); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); $data = curl_exec($ch); $errno = curl_errno($ch); if ($errno>0) {$data = false; } curl_close($ch); return $data;}function microtime_float(){ list($usec, $sec) = explode(' ', microtime()); return ((float)$usec + (float)$sec);}$url_arr=array( 'taobao'=>'http://www.taobao.com', 'sohu'=>'http://www.sohu.com', 'sina'=>'http://www.sina.com.cn',);$time_start = microtime_float();$data=array();foreach ($url_arr as $key=>$val){ $data[$key]=curl_fetch($val);}$time_end = microtime_float();$time = $time_end - $time_start;echo '耗時:{$time}';?>

耗時:0.614秒

<?phpfunction curl_multi_fetch($urlarr=array()){ $result=$res=$ch=array(); $nch = 0; $mh = curl_multi_init(); foreach ($urlarr as $nk => $url) {$timeout=2;$ch[$nch] = curl_init();curl_setopt_array($ch[$nch], array( CURLOPT_URL => $url, CURLOPT_HEADER => false, CURLOPT_RETURNTRANSFER => true, CURLOPT_TIMEOUT => $timeout,));curl_multi_add_handle($mh, $ch[$nch]);++$nch; } /* wait for performing request */ do {$mrc = curl_multi_exec($mh, $running); } while (CURLM_CALL_MULTI_PERFORM == $mrc); while ($running && $mrc == CURLM_OK) {// wait for networkif (curl_multi_select($mh, 0.5) > -1) { // pull in new data; do {$mrc = curl_multi_exec($mh, $running); } while (CURLM_CALL_MULTI_PERFORM == $mrc);} } if ($mrc != CURLM_OK) {error_log('CURL Data Error'); } /* get data */ $nch = 0; foreach ($urlarr as $moudle=>$node) {if (($err = curl_error($ch[$nch])) == ’’) { $res[$nch]=curl_multi_getcontent($ch[$nch]); $result[$moudle]=$res[$nch];}else{ error_log('curl error');}curl_multi_remove_handle($mh,$ch[$nch]);curl_close($ch[$nch]);++$nch; } curl_multi_close($mh); return $result;}$url_arr=array( 'taobao'=>'http://www.taobao.com', 'sohu'=>'http://www.sohu.com', 'sina'=>'http://www.sina.com.cn', );function microtime_float(){ list($usec, $sec) = explode(' ', microtime()); return ((float)$usec + (float)$sec);}$time_start = microtime_float();$data=curl_multi_fetch($url_arr);$time_end = microtime_float();$time = $time_end - $time_start; echo '耗時:{$time}';?>

耗時:0.316秒 帥氣吧整個頁面訪問后端接口的時間節省了一半

原文：http://www.searchtb.com/2010/12/using-multicurl-to-improve-performance.html