The Bluehost CPU quota defined:

The CPU quota is calculated using a set number of runtime CPU seconds over a set number of realtime seconds.

With us, if you use more than 40 CPU seconds over a 60 realtime second period, the cpu quota system will suspend the website until the average over the last three minutes is below 40 CPU seconds. The three minute average is calculated every 15 seconds for the previous three minutes. As soon as your average is below the 40 CPU seconds, you will be unsuspended.

Also, processes are not terminated for going over the quota, as we don’t like killing half done processes. After the process finishes, it’s entire CPU usage is added into the last minute of processes.

If you have 200 processes in a minute that each use .5 CPU seconds, it will get you suspended. If those same processes take two minutes, you won’t get suspended.

Since the last sentence didn’t make any sense Alligosh later clarified that he meant to say .4 CPU seconds which makes sense again.