The actual computational work this app is going to be doing is rather small (waiting on IO). I would be more concerned about wasting memory leaving this running all the time.
I remember seeing Ruby on Rails constantly burning something like 10% CPU even when it was ostensibly only waiting on the machine (though this might be an issue that has been fixed since, I am not particularly optimistic given the day and age), and anyhow, even in the RAM department, I only have 512MB to work with (of which most is in use most of the time anyway).
