The cpu usage jumps to 100% and stays there when I turn the quarry on, and goes back to normal 50% ish when I turn it off. (idle cpu usage is with minecraft running aswell..)
The map I use is imported from a SSP world if that means anything, it is only me and my brother playing on the server. There is no lag, but I am concerned cause my stock fan is getting real crappy, and when this one core jumps to 100% while the others are working hard the cpu gets real hot, like close to 100 degrees C.