这个问题困扰了我几次,其中一个是在php循环中使用curl的正确方法
$ch = curl_init();
for($i=0; $i<10; $i++){
// curl options skiped ..
curl_setopt($ch,CURLOPT_URL,"https://secure.imvu.com/login/login/");
$response = curl_exec($ch);
// print $response;
}
curl_close($ch);
或
for($i=0; $i<10; $i++){
$ch = curl_init();
// curl options skiped ..
curl_setopt($ch,CURLOPT_URL,"https://secure.imvu.com/login/login/");
$response = curl_exec($ch);
// print $response;
curl_close($ch);
}
为什么?
从我的想法来看,第一个摆脱滞后并使用比第二个更低的进程,因为第二个需要打开和关闭每个循环上的curl处理程序,这会产生很多进程,curl_close();
调用后保存,因此只要它没有在循环中关闭,我将无法删除它< / p>
我需要知道哪一个更合适,为什么,各有利弊。
答案 0 :(得分:3)
从性能角度来看无关紧要 - 选择能够补充其余脚本所需功能的方法。与发出HTTP请求所花费的时间相比,运行curl_init()所需的时间是一个短暂的。
我测试了这两个小脚本。第一次运行3,293.014ms,第二次运行3,176.957ms。这看起来有点违反直觉,因为第二个脚本会重复比第一个脚本更多的指令。但是当你查看这两者之间的时间差时,每个请求大约相当于6毫秒,这可能会在“舍入错误”范围内下降,整个过程发出20个HTTP请求需要6秒。
如果您想自己测试一下,可以在下面找到该代码。
<?php // RAY_class_Stopwatch.php
error_reporting(E_ALL);
// DEMONSTRATE A SCRIPT TIMER FOR ALL OR PART OF A SCRIPT PHP 5+
// MAN PAGE http://php.net/manual/en/function.microtime.php
class StopWatch
{
protected $a; // START TIME
protected $s; // STATUS - IF RUNNING
protected $z; // STOP TIME
public function __construct()
{
$this->a = array();
$this->s = array();
$this->z = array();
}
public function __destruct()
{
$ret = $this->readout();
if (!$ret) return FALSE;
echo
__CLASS__
. '::'
. __FUNCTION__
. '() '
;
echo "<b>$ret</b>";
echo PHP_EOL;
}
// A METHOD TO REMOVE A TIMER
public function reset($name='TIMER')
{
// RESET ALL TIMERS
if ($name == 'TIMER')
{
$this->__construct();
}
else
{
unset($this->a[$name]);
unset($this->s[$name]);
unset($this->z[$name]);
}
}
// A METHOD TO CAPTURE THE START TIME
public function start($name='TIMER')
{
$this->a[$name] = microtime(TRUE);
$this->z[$name] = $this->a[$name];
$this->s[$name] = 'RUNNING';
}
// A METHOD TO CAPTURE THE END TIME
public function stop($name='TIMER')
{
$ret = NULL;
// STOP ALL THE TIMERS
if ($name == 'TIMER')
{
foreach ($this->a as $name => $start_time)
{
// IF THIS TIMER IS STILL RUNNING, STOP IT
if ($this->s[$name])
{
$this->s[$name] = FALSE;
$this->z[$name] = microtime(TRUE);
}
}
}
// STOP ONLY ONE OF THE TIMERS
else
{
if ($this->s[$name])
{
$this->s[$name] = FALSE;
$this->z[$name] = microtime(TRUE);
}
else
{
$ret .= "ERROR: CALL TO STOP() METHOD FOR '$name' IS NOT RUNNING";
}
}
// RETURN AN ERROR MESSAGE, IF ANY
return $ret;
}
// A METHOD TO READ OUT THE TIMER(S)
public function readout($name='TIMER', $dec=3, $m=1000, $eol=PHP_EOL)
{
$str = NULL;
// GET READOUTS FOR ALL THE TIMERS
if ($name == 'TIMER')
{
foreach ($this->a as $name => $start_time)
{
$str .= $name;
// IF THIS TIMER IS STILL RUNNING UPDATE THE END TIME
if ($this->s[$name])
{
$this->z[$name] = microtime(TRUE);
$str .= " RUNNING ";
}
else
{
$str .= " STOPPED ";
}
// RETURN A DISPLAY STRING
$lapse_time = $this->z[$name] - $start_time;
$lapse_msec = $lapse_time * $m;
$lapse_echo = number_format($lapse_msec, $dec);
$str .= " $lapse_echo";
$str .= $eol;
}
return $str;
}
// GET A READOUT FOR ONLY ONE TIMER
else
{
$str .= $name;
// IF THIS TIME IS STILL RUNNING, UPDATE THE END TIME
if ($this->s[$name])
{
$this->z[$name] = microtime(TRUE);
$str .= " RUNNING ";
}
else
{
$str .= " STOPPED ";
}
// RETURN A DISPLAY STRING
$lapse_time = $this->z[$name] - $this->a[$name];
$lapse_msec = $lapse_time * $m;
$lapse_echo = number_format($lapse_msec, $dec);
$str .= " $lapse_echo";
$str .= $eol;
return $str;
}
}
}
// DEMONSTRATE THE USE -- INSTANTIATE THE STOPWATCH OBJECT
$sw = new Stopwatch;
// TIME OSA'S SCRIPTS
ob_start();
$sw->start('ENTIRE');
$sw->start('FIRST');
$ch = curl_init();
for($i=0; $i<10; $i++){
// curl options skiped ..
curl_setopt($ch,CURLOPT_URL,"https://secure.imvu.com/login/login/");
$response = curl_exec($ch);
// print $response;
}
curl_close($ch);
$sw->stop('FIRST');
$sw->start('SECOND');
for($i=0; $i<10; $i++){
$ch = curl_init();
// curl options skiped ..
curl_setopt($ch,CURLOPT_URL,"https://secure.imvu.com/login/login/");
$response = curl_exec($ch);
// print $response;
curl_close($ch);
}
$sw->stop('SECOND');
$sw->stop('ENTIRE');
ob_end_clean();
$sw->readout();
最好的,〜雷