[edit] Last updated: Fri, 25 May 2012

set_time_limit

(PHP 4, PHP 5)

set_time_limit — Limita el tiempo máximo de ejecución

Descripción

void set_time_limit ( int $seconds )

Establece el número de segundos que se permite la ejecución de un script. Si esto se alcanza, el script devuelve un error fatal. El límite predeterminado es de 30 segundos o, si es que existe, el valor max_execution_time definido en el php.ini.

Cuando es llamado, set_time_limit() reinicia el contador de tiempo de espera de cero. En otras palabras, si el tiempo de espera por defecto es de 30 segundos, y 25 segundos en la ejecución del script se hace la llamada set_time_limit(20), el script se ejecutará durante un total de 45 segundos antes de que se agote el tiempo.

Parámetros

seconds: El tiempo de ejecución máximo, en segundos. Si se pone a cero se impone sin límite de tiempo.

Valores devueltos

No devuelve ningún valor.

Notas

Advertencia

Esta función no tiene efecto cuando PHP se ejecuta en safe mode. No hay ninguna solución más que deshabilitar el modo seguro o cambiar el tiempo límite en el php.ini.

Nota:
La función set_time_limit() y la directiva de configuración max_execution_time sólo afectan el tiempo de ejecución del script mismo. Todo el tiempo dedicado a la actividad que ocurre fuera de la ejecución del script, como las llamadas al sistema usando system(), operaciones de secuencia, consultas a la bases de datos, etc. No se incluyen cuando se determina el tiempo máximo del script en funcionamiento. Esto no es cierto en Windows, donde el tiempo medido es real.

Ver también

sys_get_temp_dir

set_magic_quotes_runtime

[edit] Last updated: Fri, 25 May 2012

add a note User Contributed Notes set_time_limit

mingalevme at gmail dot com 10-May-2012 07:51


If you're using PHP_CLI SAPI and getting error "Maximum execution time of N seconds exceeded" where N is an integer value, try to call set_time_limit(0) every M seconds or every iteration. For example:



<?php



require_once('db.php');



$stmt = $db->query($sql);



while ($row = $stmt->fetchRow()) {

    set_time_limit(0);

    // your code here

}



?>

ratty at brohoof dot com 25-Nov-2011 07:39


One thing that I wish I had found sooner is, if you're using php-cli and really need to limit the executation time, and if you're in *nix, you can use "timeout" which is part of coreutils.

For example:



timeout 5 /usr/bin/php -q /path/to/script



and it will kill it if it takes longer than 5 seconds.

I had a few quick php scripts I wrote for use with cacti for example.

alexander dot krause at ed-solutions dot de 29-Aug-2011 02:26


A nice workaround to have a real max_execution_time (needs posix and pcntl):





<?php


$pid=pcntl_fork();





if ($pid) {


  //long time process


  $a=0;


  while (true) {


    echo "a=$a\n\n";


    ob_flush();


    flush();


    $a++;


    shell_exec('sleep 10&');


  }


} else {


  //time-limit checker


  sleep(5);


  posix_kill(posix_getppid(),SIGKILL);


}


?>

agvozden at gmail dot com 01-Oct-2010 01:51


If you got something like:





msg: set_time_limit() [function.set-time-limit]: Cannot set time limit in safe mode 





try this:





<?php


        if( !ini_get('safe_mode') ){


            set_time_limit(25);


        }


?>

kamazee at gmail dot com 21-Sep-2010 06:39


Keep in mind that for CLI SAPI max_execution_time is hardcoded to 0. So it seems to be changed by ini_set or set_time_limit but it isn't, actually.

The only references I've found to this strange decision are deep in bugtracker (http://bugs.php.net/37306) and in php.ini (comments for 'max_execution_time' directive).

Silver_Knight 23-Mar-2010 05:18


if you are running a script that needs to execute for unknown time, or forever.. you may use

set_time_limit(0);

.....

...

..

.

and at the end of the script use flush() function to tell phpto send out what it has generated.

ravenswd at gmail dot com 15-Aug-2009 04:46


Unfortunately, a script which gets into an infinite loop can produce an alarming amount of output in only a few seconds. I was attempting to debug a script, and I added



<?php

set_time_limit(2);

?>



to the beginning of the script. Unfortunately, even two seconds of run time produced enough output to overload the memory available to my browser.



So, I wrote a short routine which would limit the execution time, and also limit the amount of output returned. I added this to the beginning of my script and it worked perfectly:



<?php

set_time_limit(2);



ob_start();     // buffer output



function shutdown () {

    // print only first 2000 characters of output

    $out = ob_get_clean();

    print substr($out, 0, 2000);

}



register_shutdown_function('shutdown');

?>

BW 16-May-2009 05:08


If you use Apache you can change maximum execution time by .htaccess with this line



php_value max_execution_time 200

cweiske at cweiske dot de 02-Sep-2008 04:38


To get the currently used time, use getrusage()

jonathon dot keogh at gmail dot com 18-Jul-2008 02:07


You can do set_time_limit(0); so that the script will run forever - however this is not recommended and your web server might catch you out with an imposed HTTP timeout (usually around 5 minutes).



You should check your web server's guides for more information about HTTP timeouts.



Jonathon

gib at pganet dot com 20-Jun-2008 12:25


if you are using win2008server, iis7, then before using this option, do not forget to set some variables.



at:



%windir%\system32\inetsrv\



directory, execute the following commands to set the max time to 300 sec. (replace the PHPDIR and PHPEXE with the real ones):



appcmd set config /section:system.webServer/fastCGI /[fullPath='PHPDIR\PHPEXE'].activityTimeout:300

appcmd set config /section:system.webServer/fastCGI /[fullPath='PHPDIR\PHPEXE'].requestTimeout:300



If you want to make double-check that the configuration worked properly, you can check it like this:



appcmd list config -section:system.webServer/fastCgi

AtlantisNet 04-Jun-2008 12:08


In IIS, there is another global timeout setting which will override any PHP settings.  You can alter this timeout by following the following instructions:



http://www.iisadmin.co.uk/?p=7

riki1512 05-Jun-2007 05:29


Please note that, under Linux, sleeping time is ignored, but under Windows, it counts as execution time.

php at stock-consulting dot com 12-Jan-2007 05:30


To find out the currently set time limit, use





<?php


 ini_get('max_execution_time');


?>





If set_time_limit has been previously called in the script, the result will be the value which was passed to set_time_limit (and not, as the function name "ini_get" appears to suggest, the value from the php.ini file).

bjfieldNO at SPAMgmail dot com 10-Jan-2007 02:53


Timeouts after five minutes in IIS on Windows are caused by an inherited CGI Timeout value of 300 seconds.  This is not a PHP problem.  The fix is to add custom values for the files or directories that need longer to run.



In IIS 5.0 or 7.0 (beta as of this note), you can change this value on a fairly granular level using IIS Manager, under (roughly) YOURSITE -> Properties -> Home Directory -> Configuration (button) -> Options, but in IIS 6.0, this functionality is turned off (!), so you have to get into the Metabase.



Find the site number in Metabase Explorer (e.g., 12345678), then from CMD prompt:



[get to the scripts dir]

cd C:\Inetpub\AdminScripts



[this for each subdirectory from off the site root]

cscript adsutil.vbs CREATE W3SVC/12345678/root/"MY SUBDIRECTORY" IIsWebDirectory



[this for the file in question]

cscript adsutil.vbs CREATE W3SVC/12345678/root/"MY SUBDIRECTORY"/ILikeToTimeOut.php IIsWebFile



[this to set the timeout]

cscript adsutil.vbs set W3SVC/12345678/root/"MY SUBDIRECTORY"/ILikeToTimeOut.php/CGITimeout "7200"



Note:  "7200" is 2 hours in seconds, but can be whatever.



I derived the solution above from this fine article:

http://www.iis-resources.com/modules/AMS/article.php?

storyid=509&page=3

mba_aslam at yahoo dot com 05-Jan-2007 05:50


while setting the set_time_limit(), the duration of sleep() will be ignored in the execution time. The following illustrates:



<?php



set_time_limit(20);



while ($i<=10)

{

        echo "i=$i ";

        sleep(100);

        $i++;

}



?>



Output:

i=0 i=1 i=2 i=3 i=4 i=5 i=6 i=7 i=8 i=9 i=10

27-Sep-2006 02:03


After the error



Fatal error: Maximum execution time of [...] seconds exceeded [...]



has appeared, shut-down functions are still called (afterwards). So, by using register_shutdown_function, you can save data in a session and offer the user a link to start the script again. Then the script can go on with the Session-data.



Example: if you are analyzing a text-file, you can save your analyzed data in a session together with the position of the filepointer (ftell) and start from that possition the next time the user runs the script (fseek). 



To determine whether the script was finished or aborted, you simply set a bool false at the beginning and true at the end, and in the shutdown-function you check if it's still false.

konrads dot smelkovs at gmail dot com 01-Apr-2006 06:35


If you are streaming large data from database, it is counted towards the max exec time.

jatin at jatinchimote dot com 01-Mar-2006 10:54


If you set the number of seconds to a very large number (not many ppl do that, but just in case) then php exits with a fatal error like :





Fatal error: Maximum execution time of 1 second exceeded in /path/to/your/script/why.php





[EDIT by danbrown AT php DOT net: This is due to the limit of 32-bit signed integers.]

Cleverduck 28-Feb-2006 01:36


Regarding what 'nytshadow' said, it's important to realize that max-execution-time and the set_time_limit functions measure the time that the CPU is working on the script.  If the script blocks, IE: for input, select, sleep, etc., then the time between blocking and returning is NOT measured.  This is the same when running scripts from the command line interface.  So if you've got a log parser written in PHP that tails a file, that program WILL fail eventually.  It just depends how long it takes to read in enough input to process for 30 seconds.



If you're writing a command line script that should run infinitely, setting max-execution-time to 0 (never stop) is HIGHLY recommended.

rycardo74 at gmail dot com 24-Nov-2005 10:52


this work to fine html streaming AND time pass limit





<?php


header('Content-type: text/plain');


echo date("H:m:s"), "\n";


set_time_limit(30);


for ($i = 0; $i < 1000; $i++)


{





    echo date("H:m:s"),"\n";


    for ($r = 0; $r < 100000; $r++){


    $X.=  tan(M_LNPI+log(ceil(  date("s")*M_PI*M_LNPI+100)));


    }


    ob_flush();   


    flush();





}


echo "work! $x";


?>

nytshadow 14-Jul-2005 08:15


This tripped me up for a bit until I read through the ini settings.  When doing file uploads, max_execution_time does not affect the time even though the error message indicates the script has exceeded the maximum execution time.  The max_input_time determines how much time PHP will wait to receive file data.  The default setting is 60 seconds so while I had my max_execution_time set to 300, the script would fail after 60 seconds but report that it had exceeded the max execution time of 300.

Sjoerd van der Hoorn 21-Jun-2005 03:08


When using the set_time_limit() function, the browser will stop after about 30 seconds if it does not get new data. To prevent this, you can send every 10 seconds a little snippet of data (like a single character) to the browser. The code below is tested with both Internet Explorer and Firefox, so it will stay online all the time.



You should also create a file called chatdata.txt which contains the last thing said on a chatbox. Please note that you can also replace this function with a MySQL or other database function... 



<?php



set_time_limit(900);



// Start output buffering

ob_start();



$message = "First test message";

$oldmessage = "bla";



// Keep on repeating this to prevent PHP from stopping the script

while (true)

{

    $timeoutcounter = 0;

    while ($message == $oldmessage)

    {

        // If 10 seconds elapsed, send a dot (or any other character)

        if ($timeoutcounter == 10)

        {

            echo ".";

            flush();

            ob_flush();

            $timeoutcounter = 0;

        }

        // Timeout executing

        sleep(1);

        // Check for a new message

        $message = file_get_contents("chatdata.txt");

        $timeoutcounter++;

    }



    // Keep the old message in mind

    $oldmessage = $message;



    // And send the message to the user

    echo "<script>window.alert(\"" . $message . "\");</script>";



    // Now, clear the output buffer

    flush();

    ob_flush();

}



?>

eric pecoraro at shepard com 06-Jun-2005 12:57


I was having trouble with script timeouts in applications where the user prompted long running background actions. I wrote this cURL/CLI background script that solved the problem when making requests from HTTP.



<?php



/* BACKGROUND CLI 1.0

   

   eric pecoraro _at_ shepard dot com - 2005-06-02

   Use at your own risk. No warranties expressed or implied.



   Include this file at the top of any script to run it in the background

   with no time limitations ... e.g., include('background_cli.php');

   

   The script that calls this file should not return output to the browser. 

*/

#  REQUIREMENTS - cURL and CLI

   if ( !function_exists('curl_setopt') OR !function_exists('curl_setopt')  ) {

      echo 'Requires cURL and CLI installations.' ; exit ; 

   }

   

#  BUILD PATHS

   $script = array_pop(explode('/',$SCRIPT_NAME)) ; 

   $script_dir = substr($SCRIPT_NAME,0,strlen($SCRIPT_NAME)-strlen($script)) ;

   $scriptURL = 'http://'. $HTTP_HOST . $script_dir . "$script" ;

   $curlURL = 'http://'. $HTTP_HOST . $script_dir . "$script?runscript=curl" ;



#  Indicate that script is being called by CLI 

   if ( php_sapi_name() == 'cli' ) {

      $CLI = true ;

   }



#  Action if script is being called by cURL_prompt()

   if ( $runscript == 'curl' ) {

      $cmd = "/usr/local/bin/php ".$PATH_TRANSLATED ; // server location of script to run

      exec($cmd) ;

      exit;

   }



#  USER INTERFACE

   // User answer after submission.

   if ( $post ) {

      cURL_prompt($curlURL) ;

      echo '<div style="margin:25px;"><title>Background CLI</title>';

      echo 'O.K. If all goes well, <b>'.$script.'</b> is working hard in the background with no ' ;

      echo 'timeout limitations. <br><br><form action='.$scriptURL.' method=GET>' ;

      echo '<input type=submit value=" RESET BACKGROUND CLI "></form></div>' ;

      exit ;

   }

   // Start screen.

   if ( !$CLI AND !$runscript ) {

      echo '<title>Background CLI</title><div style="margin:25px;">' ;

      echo '<form action='.$scriptURL.' method=POST>' ;

      echo 'Click to run <b>'.$script.'</b> from the PHP CLI command line, in the background.<br><br>' ;

      echo '<input type=hidden value=1 name=post>' ;

      echo '<input type=submit value=" RUN IN BACKGROUND "></form></div>' ;

      exit ;

   }



#  cURL URL PROMPT FUNCTION

   function cURL_prompt($url_path) {

      ob_start(); // start output buffer

      $c=curl_init($url_path);

      curl_setopt($c, CURLOPT_TIMEOUT, 2); // drop connection after 2 seconds

      curl_exec($c);

      curl_close($c);

      ob_end_clean(); // discard output buffer

   }

?>

php at mightycpa.com 26-Jun-2003 01:30


You may also need to look at Apache's timeout setting (Win32 version for me), I changed max execution time value in php.ini, and still got stopped by Apache's timeout value in the httpd.conf file.

rsallo at gna dot NOSPAM dot es 30-May-2003 04:28


When you are working with IIS, PHP timeout is valid only when it's lower than script timeout defined by IIS.



IIS 5 has a default timeout of 300 seconds. If you need a higher timeout, you also have to change IIS properties. Otherwise, your server will stop your PHP script before it reaches its own timeout.

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