So I am using my GPU (Nvidia GeForce GTX 850M) for scientific calculations.
After a while I realized that my calculations are far too slow.
I investigated and found a huge performance drop after suspending Ubuntu.
Here is an example with glxgears Benchmark:
- Startup Ubuntu
- run glxgears with result ~15000 FPS
- cancel glxgears and suspend
- run glxgears with result ~200 FPS
This is consistent with my scientific calculations, where performence drops to ~1/30th after suspend. (The drop is smaller because not all calculations are done on GPU)
I tested this with and nvidia-361 and nvidia-370 drivers and can't figure out why this happens.