php使用curl并发减少后端访问时间的方法分析

本文实例讲述了php使用curl并发减少后端访问时间的方法。分享给大家供大家参考，具体如下：

在我们平时的程序中难免出现同时访问几个接口的情况，平时我们用curl进行访问的时候，一般都是单个、顺序访问，假如有3个接口，每个接口耗时500毫 秒那么我们三个接口就要花费1500毫秒了，这个问题太头疼了严重影响了页面访问速度，有没有可能并发访问来提高速度呢？今天就简单的说一下，利用 curl并发来提高页面访问速度，

1、老的curl访问方式以及耗时统计

<?php
function 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 - $time_start;
 echo "耗时:{$time}";
?>

耗时:0.614秒

2、curl并发访问方式以及耗时统计

<?php
function 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 && $mrc == curlm_ok) {
    // wait for network
    if (curl_multi_select($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 - $time_start;
 echo "耗时:{$time}";
?>

耗时:0.316秒

帅气吧整个页面访问后端接口的时间节省了一半

3、curl相关参数

curl_close — close a curl session
curl_copy_handle — copy a curl handle along with all of its preferences
curl_errno — return the last error number
curl_error — return a string containing the last error for the current session
curl_exec — perform a curl session
curl_getinfo — get information regarding a specific transfer
curl_init — initialize a curl session
curl_multi_add_handle — add a normal curl handle to a curl multi handle
curl_multi_close — close a set of curl handles
curl_multi_exec — run the sub-connections of the current curl handle
curl_multi_getcontent — return the content of a curl handle if curlopt_returntransfer is set
curl_multi_info_read — get information about the current transfers
curl_multi_init — returns a new curl multi handle
curl_multi_remove_handle — remove a multi handle from a set of curl handles
curl_multi_select — wait for activity on any curl_multi connection
curl_setopt_array — set multiple options for a curl transfer
curl_setopt — set an option for a curl transfer
curl_version — gets curl version information

更多关于php相关内容感兴趣的读者可查看本站专题：《php curl用法总结》、《php数组(array)操作技巧大全》、《php数据结构与算法教程》、《php数学运算技巧总结》、《php日期与时间用法总结》、《php面向对象程序设计入门教程》、《php字符串(string)用法总结》、《php+mysql数据库操作入门教程》及《php常见数据库操作技巧汇总》

希望本文所述对大家php程序设计有所帮助。