I have an issue which stops my (slow) process. I start my background slow process using a php page with a button as follow:
<form id="trial" method="post" action=""><input name="trial" value="Start!" type="submit">
<?php
set_time_limit(0);
if (isset($_POST['trial'])) {
system("/srv/www/cgi-bin/myscript.sh");
}
?>
At some point after 1.5 days the process stops, I have modified the php.ini and the apache config file inserting a very high number in the timeout directive, but it seems it does not work, or there is some other process that is stopping myscript.sh.. do you have any suggestions?
thanks!
I'm assuming you have access to the server via SSH based on your post.
If the real goal is to get your script to run continuously, why not log in and
nohup myscript.sh
As long as your script behaves, it will continue to run as long as it needs to after you close the terminal.
Check the Logs
To determine why your script is failing, you'll definitely want to check /var/log/kern.log and /var/log/syslog. Look for any entries containing your script or any of it's children. Your script may be getting killed off by the kernel ( exceeding limits ) or erroring out at runtime.
Execute the script continuously will take some problem so set Cron for every 30 mins in your system.
set_time_limit(30);
system("/srv/www/cgi-bin/myscript.sh");
Cron setup :
30 * * * * php /path/to/your/php/file.php
Related
PHP Has a method called set_time_limit (and a config option max_execution_time), which allows you to specify a time limit which triggers the script to exit when reached. However, this does not take into account time on external calls. Which means that if (for example) the PHP script makes a database call that does something dumb and runs for hours, the set time limit will not trigger.
If I want to guarantee that my PHP script's execution time will not exceed a specific time, is there some way to do this? I'm running the script directly in PHP (rather than via apache or similar), so I'm considering writing a bash script to monitor ps and kill it after a certain time. It occurs to me that I can't be the first person with this problem though, so is there some already-built solution available for this?
Note: This question is NOT about the PHP error from exceeding it's maxed execution time. This is about the case where PHP exceeds a time limit without triggering this error. This question is NOT just about limiting the time of a PHP script, it is about limiting the time allowed to a PHP script making external calls.
When running PHP from the command line the default setting "max_execution_time" is 0.
You can try something similar to solve your problem.
$cmd = "(sleep 10 && kill -9 ".getmypid().") > /dev/null &";
exec($cmd); //issue a command to force kill this process in 10 seconds
$i=0;
while(1){
echo $i++."\n";
sleep(1); //simulating a query
}
I want to run a php script every 5 minutes that processes some simple mysql queries to identify potential errors and in case an error is recorded as a database entry the php script sends out an email.
From my research, it seems like cron jobs (or task schedulers) usually take care of running scripts at specified times, however I cannot find this option anywhere at the hosting service I am using (who runs "Parallels Plesk Panel 11.0.9" as the management interface I can access).
Therefore I tried the following "trick":
<?php
$active = $_GET["a"];
set_time_limit(0);
while($active == 1){
include 'alert_exe.php';
sleep(300); // execute script every 5 mins
}
?>
To active the script I enter the url (".../alert.php?a=1"). This works fine for a couple of minutes, however it seems after 2 or 3 minutes the script stops executing.
Any idea how I can prevent the stopping of the script or alternative suggestions how to achieve the automatic execution of a script every 5minutes (without being able to access cron jobs)?
Thanks!
It would not surprise me that a hosting service would protect its servers from getting overloaded with long-running scripts, and would configure a time-out after which such scripts are aborted (see PHP: Runtime Configuration Settings and max_execution_time in particular).
If you have a PC that can stay turned on, an alternative solution would be to let it send a request to the server every 5 minutes:
<?php
// Your PHP code that has to be executed every 5 minutes comes here
?>
<script>
setTimeout(function () { window.location.reload(); }, 5*60*1000);
// just show current time stamp to see time of last refresh.
document.write(new Date());
</script>
There is a max_execution_time parameter which stops the script if it takes too long, 30 seconds by default, see the docs - http://php.net/manual/en/info.configuration.php#ini.max-execution-time.
You can try to do set_time_limit(0) at the beginning of your script (see http://php.net/manual/en/function.set-time-limit.php), or change the max_execution_time parameter itself.
But in general, I would not go with such solution, it is not very reliable. Better find a hosting where you can use cron or you can try to look for some external service which will ping your script every 5 minutes (probably you can use services which monitor the web application health).
try this solution:
<?php
$interval=5; //minutes
set_time_limit(0);
while (true)
{
$now=time();
include("alert_exe.php");
sleep($interval*05-(time()-$now));
}
?>
Stop the script by restarting apache, or build in a return value from your internal script which changes while (true) to while (false)
I have scheduled a CRON which calls/executes a PHP script every five minutes. PHP script perform following tasks
Checks for the flag value in database to identify if the previous run is still executing. Value of 1 in the DB tells that process is still running while a value of 0 means it is not.
If the flag value is 1, then exit the PHP else continue to next step.
Update the flag value in database from 0 to 1.
Execute the business logic.
Update the flag value back from 1 to 0, so that next CRON can executes if the data is available in user tables.
All works fine so far, depending on the size of user uploaded data the process on an average takes 35 to 40 minutes to complete.
Question, Is there anyway to kill or stop the execution of PHP script once started by cron. May be a button to let users stop the execution, upload new data and wait for CRON run. I can take care of reseting all the flags and data it's just the kill of PHP script is what i am trying to figure out.
I did some google and figured i can use some commands like:
Killall -9 PHP
to kill all php processes running on server, but not sure how to do this through PHP.
Try this:
ps aux |grep 'part_of_the_name_of_your_script'|awk '{print $2}' |xargs kill -9 {}
Or in your crontab file use crun and variable CRUN_TIME
see crun -h
A lock file would be very appropriate for this tasks.
The PHP script can attempt to create a new file, and if none is created already you can safely know that the script is the only one running at the present time. If a file exists, you can simply exit the script.
Example:
<?php
if (file_exists('/var/run/my-script')) {
exit(1); // already running
}
file_put_contents('/var/run/my-script', getmypid());
/** Business Logic **/
unlink('/var/run/my-script');
exit(0);
?>
You can try system() or exec(), but it might not work (or return permission denied errors) as cron processes are executed by either the current user or root, and the web server user doesn't usually have access to these processes.
I basically have a cron job calling one script every minute. Script immediately stops, if previous script is still running (checks previous script's activity time).
So I made a bug, and the script went in to an infinite loop (I know it was called from by cron atleast one time). I created a fix and uploaded it to the server, but I'm still wondering:
How long will the bugged script run?
How can I know if it is still running?
What does terminate a script and why?
The script just echoes out the same text over and over again.
P.S. PHP's max execution time within the script is set to 0 (infinite) and I don't have a direct access to the server, only FTP.
How can I know if it is still running?
Just set up a new cron job, but have the cron command be a something that helps you debug:
a useful one would be
ps -af | grep php > /some/path/to/mylogfile.txt
the ps command lists info on running processes. with those flags, part of the output will be the original linux command that started the process, and so we can grep the line and look for php because the origional command was probably something like:
php myscript.php
the output is redirected to mylogfile.txt for you to manually read after the cron job runs.
the process id should be part of the output. you can then use the kill command on that process id, again by just entering the command as a fake cron job.
Until the script runs into an timeout(max_execution_time defined in php.ini file or set_time_limit method)
Have a look at the running processes
send kill command to the script or wait till a timeout occurs
PS: you have to php.ini files - one for command line and one for Apache - be sure to Change the max_execution_time in the commandline ini file
I'm currently running an Apache server (2.2) on my local machine (Windows) which I'm using to run some PHP scripts to take care of some tedious work. One of the scripts involves a ton of moving, resizing, and download / uploading files to another server. I would very much like the script to run constantly so that I don't have to baby the script by starting it up again every time it times out.
set_time_limit(0);
ignore_user_abort(1);
Both are set in my script, but after about 30mins to an hour the script stops and I get the 504 Gateway Time-out message in my browser. Is there something I missing in Apache or PHP to prevent the timeout? Or should I be running the script a different way?
Or should I be running the script a different way?
Definitely. You should run your script from command line (CLI)
if i should implement something like this i would you 2 different scripts:
A. process_controller.php
B. process.php
The workflow should be:
the user call the script A by using a browser
the script A start the script B by using a system() or exec() and pass to it a "process token" via command line.
the script B write the execution status into a shared space: a file named as the token, a database table. in general something that can be read also by the script A by using the token as reference
the script A contains an AJAX call, in polling, that ask to the script A the status of the process for a given token
Ajax polling:
<script>
var $myToken;
function ajaxPolling()
{
$.get('process_controller.php?action=getStatus&token='+$myToken, function(data) {
$('.result').html(data);
});
}
setInterval("ajaxPolling()",60*1000); //Every minute
</script>
there are some considerations about the communication between the 2 processes, depending on how many instances of the script B you would be able to run in parallel
Just one: you don't need a random/unique token
One per user: session_start(); $token = session_id();
More than one per user: session_start(); $token = session_id().microtime();
If you need to run it form your browser, You should make sure that there is not php execution limit in the php.ini file, but also that there is not limit set in mod_php (or what ever you are using) under apache.
Use php's system() to call a shell script which starts a service/background task.