Long running php process vs cronjob

[luckman212]

While I was working on #4595 I was thinking about ways to minimize the overhead of running a cronjob once a minute, startup up php, loading includes etc.

I thought it could be better to have the main script just run once and stay running in a loop with a sleep interval, and then instead use cron to fire off a small check job once in a while just to make sure that main task is always running. I wasn't sure if this was possible or even a good idea. Anyone have any thoughts?