ATP sensor Consume most server CPU (60%)

The sensor (if installed on a DC) will make sure at least 15% of RAM and CPU are free at all time.

other wise it will try to utilize any free resources to reduce data latency.
if the machine will get more busy, the limits will be adjusted and it will utilize less resources.

(It will auto adjust within ~ 10 sec)

Plus, if it's a new deployment, and this instance is a synchronizer candidate, it's expected to work harder during the first few hours until the initial AD sync completes.  

For a standalone sensor, it assumes it can use all the machine resources without limits.