How to monitor the GCNANO GPU load

When a GPU animation is running on the display, the related GCNANO estimated GPU load can be monitored from the GCNANO driver level, by using the following command:

 (while true; do (tr -d '\n' < /sys/kernel/debug/gc/idle | awk -F" " '{printf("gpu load %.0f%%\n", $6*100/($4-$2));}'); sleep 4; done) &

The GCNANO estimated GPU load is then periodically output in the user console as a percentage "%":

gpu load 75%
gpu load 75%
gpu load 75%


  • Stop monitoring the GPU load with the command "kill -9 `ps -o ppid= -C sleep`".
  • Adjust the GPU load update period by modifying the "sleep" value (4 seconds in the example).
  • Use the command "dmesg -n8" to mix both user and kernel console outputs.
  • Debugfs configuration needs to be enabled.
  • The detailed calculation is: GPU load = On/(End-Start) with "On, End & Start" coming from the command:
 cat /sys/kernel/debug/gc/idle
Start:   3488941301162 ns
End:     3549591148649 ns
On:      26672154276 ns
Off:     0 ns