drupal maximum execution time of cron

Question

Whats the maximum execution time of cron. is it possible to modify it if so any side effects.

Answer 1

The accepted answer above is INCORRECT. Cron's time limit in Drupal is hardcoded to 240 seconds. See the drupal_cron_run function in includes/common.inc, specifically these lines:

drupal_set_time_limit(240);

and

if (!lock_acquire('cron', 240.0)) {

(based on the source of Drupal 7.12)

So, there is no way to change this globally without hacking core. I have heard it suggested to call drupal_set_time_limit yourself inside of your hook_cron implementation, as doing so resets PHP's counter. However that won't help you when it's a third-party module implementing hook_cron.

Answer 2

Maximum execution time for Drupal's cron depends on your php.ini.

For example if you use wget -O - -q -t 1 http://www.example.com/cron.php as your cron command, apache's php.ini is used to determine the maximum execution time.

If you use php -f cron.php as your cron command, then php-cli's php.ini is used to determine the maximum execution time.

It is recommended to use php-cli for higher execution time, where you can set the maximum execution time from /etc/php5/cli/php.ini (if you use debian linux) and have no side effects on apache while cron runs.