empty cuda
> sudo fuser -v /dev/nvidia*
USER PID ACCESS COMMAND
/dev/nvidia0: root 1256 F...m Xorg
username 2057 F...m compiz
username 2759 F...m chrome
username 2777 F...m chrome
username 20450 F...m python
username 20699 F...m python
> sudo kill -9 -the python PIDs-