Scheduling commands by system inactivity So `cron` or `at` can schedule our commands to run at the exact time we need them to, but can we schedule commands to run when systems are **inactive**? Something like: echo "some_commands" | when 'cpu < 15%'

hmmm... I don't think so... but what you could do is cron a script to run like every 5 minutes and check the _load average_ to see if it's acceptably low. I wouldn't check the _current_ because you could get the cpu in between 2 really high peaks. This is just thoughts on what I'd do to accomplish this, but there might be a better way.