为了强制执行max_execution_time限制,PHP必须跟踪特定脚本所使用的CPU时间。
是否有一种方法可以在脚本中访问它?我希望在测试中包含一些关于实际PHP中消耗了多少CPU的日志记录(当脚本等待数据库时,时间不会增加)。
我用的是Linux机顶盒。
为了强制执行max_execution_time限制,PHP必须跟踪特定脚本所使用的CPU时间。
是否有一种方法可以在脚本中访问它?我希望在测试中包含一些关于实际PHP中消耗了多少CPU的日志记录(当脚本等待数据库时,时间不会增加)。
我用的是Linux机顶盒。
当前回答
我写了一个检查剩余执行时间的函数。
警告:执行时间计数在Windows和Linux平台上是不同的。
/**
* Check if more that `$miliseconds` ms remains
* to error `PHP Fatal error: Maximum execution time exceeded`
*
* @param int $miliseconds
* @return bool
*/
function isRemainingMaxExecutionTimeBiggerThan($miliseconds = 5000) {
$max_execution_time = ini_get('max_execution_time');
if ($max_execution_time === 0) {
// No script time limitation
return true;
}
if (strtoupper(substr(PHP_OS, 0, 3)) === 'WIN') {
// On Windows: The real time is measured.
$spendMiliseconds = (microtime(true) - $_SERVER["REQUEST_TIME_FLOAT"]) * 1000;
} else {
// On Linux: Any time spent on activity that happens outside the execution
// of the script such as system calls using system(), stream operations
// database queries, etc. is not included.
// @see http://php.net/manual/en/function.set-time-limit.php
$resourceUsages = getrusage();
$spendMiliseconds = $resourceUsages['ru_utime.tv_sec'] * 1000 + $resourceUsages['ru_utime.tv_usec'] / 1000;
}
$remainingMiliseconds = $max_execution_time * 1000 - $spendMiliseconds;
return ($remainingMiliseconds >= $miliseconds);
}
使用:
while (true) {
// so something
if (!isRemainingMaxExecutionTimeBiggerThan(5000)) {
// Time to die.
// Safely close DB and done the iteration.
}
}
其他回答
talal7860回答的简短版本
<?php
// At start of script
$time_start = microtime(true);
// Anywhere else in the script
echo 'Total execution time in seconds: ' . (microtime(true) - $time_start);
正如所指出的,这是“wallclock时间”而不是“cpu时间”
进一步扩展Hamid的回答,我写了一个可以重复启动和停止的helper类(用于在循环中进行分析)。
class ExecutionTime
{
private $startTime;
private $endTime;
private $compTime = 0;
private $sysTime = 0;
public function Start(){
$this->startTime = getrusage();
}
public function End(){
$this->endTime = getrusage();
$this->compTime += $this->runTime($this->endTime, $this->startTime, "utime");
$this->systemTime += $this->runTime($this->endTime, $this->startTime, "stime");
}
private function runTime($ru, $rus, $index) {
return ($ru["ru_$index.tv_sec"]*1000 + intval($ru["ru_$index.tv_usec"]/1000))
- ($rus["ru_$index.tv_sec"]*1000 + intval($rus["ru_$index.tv_usec"]/1000));
}
public function __toString(){
return "This process used " . $this->compTime . " ms for its computations\n" .
"It spent " . $this->systemTime . " ms in system calls\n";
}
}
当PHP中有闭包功能时,为什么我们不从中获益呢?
function startTime(){
$startTime = microtime(true);
return function () use ($startTime){
return microtime(true) - $startTime;
};
}
现在,在上述函数的帮助下,我们可以像这样跟踪时间
$stopTime = startTime();
//some code block or line
$elapsedTime = $stopTime();
每次调用startTime函数都会启动一个单独的时间跟踪器。所以你可以想启动多少就启动多少,也可以在任何你想要的地方停止它们。
developerfusion.com的Gringod给出了一个很好的答案:
<!-- put this at the top of the page -->
<?php
$mtime = microtime();
$mtime = explode(" ",$mtime);
$mtime = $mtime[1] + $mtime[0];
$starttime = $mtime;
;?>
<!-- put other code and html in here -->
<!-- put this code at the bottom of the page -->
<?php
$mtime = microtime();
$mtime = explode(" ",$mtime);
$mtime = $mtime[1] + $mtime[0];
$endtime = $mtime;
$totaltime = ($endtime - $starttime);
echo "This page was created in ".$totaltime." seconds";
;?>
从(http://www.developerfusion.com/code/2058/determine-execution-time-in-php/)
您可能只想知道部分脚本的执行时间。为部分或整个脚本计时的最灵活的方法是创建3个简单的函数(这里给出了过程代码,但您可以通过在它周围放置类timer{}并进行一些调整将其转换为类)。这段代码工作,只需复制粘贴并运行:
$tstart = 0;
$tend = 0;
function timer_starts()
{
global $tstart;
$tstart=microtime(true); ;
}
function timer_ends()
{
global $tend;
$tend=microtime(true); ;
}
function timer_calc()
{
global $tstart,$tend;
return (round($tend - $tstart,2));
}
timer_starts();
file_get_contents('http://google.com');
timer_ends();
print('It took '.timer_calc().' seconds to retrieve the google page');