PHP will timeout and exit with the following error once it reaches the maximum allowed time for it to execute your scripts;

Fatal error: Maximum execution time of 30 seconds exceeded in yourscript.php

You can avoid this error by increasing the maximum execution time for PHP. This can be set globally or from within your PHP scripts via any of these options;

This approach will affect all the PHP scripts running in your system. It's the best solution if you're running content management system or framework like Wordpress or Drupal as you don't need to configure the option manually to all the affected scripts.

Set the max_execution_time in your PHP configuration file to the number of seconds that want to allow your PHP scripts to execute.

1. Edit php.ini file using your favourite editor.

   $ sudo vi /etc/php/7.2/apache2/php.ini

   PHP configuration files

2. Look for max_execution_time directive.

   ; Maximum execution time of each script, in seconds
   ; http://php.net/max-execution-time
   ; Note: This directive is hardcoded to 0 for the CLI SAPI
   max_execution_time = 30

3. Change the value for max_execution_time in seconds.

   max_execution_time = 300

   Setting it to 0 will impose no time limit whatsoever to the execution of your PHP scripts.

   It's not recommended to set the value to 0 at this level as this method's system-wide change will cause any misbehaved PHP scripts to unnecessarily consume precious CPU time.

4. Restart your web server.

   $ sudo systemctl restart apache2

   Restart Apache service

This is basically the same as the previous solution, but it's actually a function that you call from your PHP script. It's a general function to override any configuration options set in your PHP's configuration file and will only affect the execution of the scripts that call the function.

When placed at the start of your PHP script, the following function call will allow it to run for 300 seconds (5 minutes).

ini_set('max_execution_time', 300)

For CMS and frameworks, it should be placed in shared files such as the configuration files. For Wordpress it's wp-settings.php.

This is PHP's built-in function specifically to set the maximum execution time limit of your PHP scripts. It's to be called from your PHP script as in the previous method and the following example is to also set the limit to 300 seconds (5 minutes).

set_time_limit ( 300 )

This is the best option if you don't have administrator access to your system but still want to set the option to all your scripts in your project folder.

Add the following lines to .htaccess file within your PHP project folder and this will be applied to all the scripts within that folder.

<IfModule mod_php7.c>
php_value max_execution_time 300
</IfModule>

The option is readily available in cPanel's dashboard and can be used to change PHP's maximum execution time limit.