Hi,

I have a web based printing application based on CUPS with billing system for a small lab. Whenever somebody prints from windows machines, it holds the print job and users can release it from the web interface.

Lab admins very often need to print a specific page. So, I don't want the printer to hold jobs for that specific job. I tried to configure CUPS, but I couldn't find such option in it, so I decided to create a script that checks all the held print jobs and release them if they're meeting the condition. I'm planning to create a cronjob that runs this script every five seconds.

The machine connected to the webserver is running a web based application for the internal use and it doesn't have a heavy load. I'm wondering if it is a good practice to run a script every five seconds?

Thanks,

You can't use cron to run a script every 5 seconds. The maximum resolution is once per minute.

The limit in cron is once per minute, but quite frankly if you want more freq than every 5 mins, I'd write a daemon that just loops and waits some time at the bottom of the loop. Its not worth hammering the system with creating a new process (from cron) every minute or 2, esp if they might overlap. Its a waste of resource.

Thanks for responds. I was thinking about wasting the resources by running cron every five seconds, too. I just didn't know any other option. I think having an infinitive loop that sleeps for 5 seconds at the end of each loop is not a good practice, either.

I guess I have to find the solution of my problem by playing around with CUPS setting.

The sleeping is not a problem - don't worry about that. Its the load that the other part of your script that you need to consider. If your system isn't doing much else, don't worry about it.