在php的手册里面有一段代码:
$mrc = curl_multi_init(); //发出请求 ....... $active = null; do { $mrc = curl_multi_exec($mh, $active); } while ($mrc == CURLM_CALL_MULTI_PERFORM); while ($active && $mrc == CURLM_OK) { if (curl_multi_select($mh) != -1) { do { $mrc = curl_multi_exec($mh, $active); } while ($mrc == CURLM_CALL_MULTI_PERFORM); } } //下面是处理请求返回的结果
这段do...while是用来控制并发的,效果是将$mrc所有的请求完毕,再执行response结果
但如果我有1000个请求,那么curl批处理将并发1000个请求,显然是不合理,所以应该要控制一个并发数,并且将剩余的连接添加到请求队列里:
参考:http://www.onlineaspect.com/2009/01/26/how-to-use-curl_multi-without-blocking/
$mh = curl_multi_init(); $ch = array(); $chunck = 10; //并发控制数 $all = count($urls);//所有的请求url数组 $chunck = $all > $chunck ? $chunck : $all; $options = array( CURLOPT_HEADER=>FALSE, CURLOPT_RETURNTRANSFER=>TRUE, CURLOPT_FOLLOWLOCATION=>TRUE, CURLOPT_MAXREDIRS=>5, CURLOPT_USERAGENT=>'Mozilla/5.0 (Windows NT 6.1; rv:6.0) Gecko/20100101 Firefox/6.0' ); for($i = 0 ; $i < $chunck ; $i++){ $ch[$i] = curl_init(); curl_setopt($ch[$i],CURLOPT_URL,$urls[$i]); curl_setopt_array($ch[$i],$options); curl_multi_add_handle($mh,$ch[$i]); } do { while(($execrun = curl_multi_exec($mh, $running)) == CURLM_CALL_MULTI_PERFORM); if($execrun != CURLM_OK)break; // a request was just completed -- find out which one while($done = curl_multi_info_read($mh)) { //获取已经返回的url在urls数组里德的index $index = array_search($done['handle'],$ch); $info = curl_getinfo($done['handle']); if ($info['http_code'] == 200){ $output = curl_multi_getcontent($ch[$index]); // request successful. process output using the callback function. $save_path = $i.'.txt';//数据保存路径 file_put_contents($save_path,$output); // start a new request (it's important to do this before removing the old one) $next = $i++;// increment i $ch[$next] = curl_init(); $options[CURLOPT_URL] = $urls[$next];//将下一个请求添加到队列 curl_setopt_array($ch[$next],$options); curl_multi_add_handle($mh, $ch[$next]); // remove the curl handle that just completed curl_multi_remove_handle($mh, $done['handle']); } else { // request failed. add error handling. } } } while ($running); curl_multi_close($mh);
使用下来效果很好,没有副作用,并发数可控,应用之处多多,自己发挥想象吧