Flying Fox wrote:
CPU folding is good because the OS scheduler does a good job shuffling low priority processes/threads. However, GPU "threads" don't get the same treatment. So the best is still to pause/shutdown the GPU client before you launch anything that uses the GPU non-trivially.
I noticed this when I first started folding last year on the main machine with the 660 Ti. I had accepted that doing much else while GPU folding would not be acceptable.
That's pretty typical. If you use GPU-Z you can measure your GPU load utilization... for GPUs hitting 100% loads under Folding@home you are going to either have to endure the lag or turn off GPU folding when using the computer. Flash video will frame skip heavily, and anything in VLC occasionally develop artifacts as well. VLC will also skip frames when this happens unless you disable it in settings. GPU Folding used to be fairly inefficient, my GTX 480 would see ~60% load utilization on average a few years ago. At 60% it barely affected light games and didn't affect video or flash video playback. Today it gets a permanent 100% load utilization because F@H is fully optimized for the card... as new GPUs get fully optimized for they will also experience the same effects.
The "light" setting in Folding@home doesn't really apply to GPUs. I've tested it and either the GPU folding is off... or it is on. There doesn't seem to be a middle-ground option. If you aren't experiencing system lag during games then odds are it turned GPU folding off when set to the "light" load profile.
Flying Fox is correct, GPU scheduling doesn't work the same as CPU scheduling.... one can play games with minimal FPS loss during CPU folding, but that just isn't the case with GPU folding. You'll need to turn off GPU folding when using your system or simply endure it. Given most web browsers now use GPU acceleration they will also lag during GPU folding, so I flat out turn off GPU folding until I'm done with the system.
Until recently I would've 100% agreed with everything you said, Kougar. Even playing FTL while folding on the GPU resulted in stuttering that had me pausing it (or setting it to "Light", pausing the GPU side). But then I noticed that there wasn't any stuttering on the machine with the 750 Ti. One day I forgot to pause folding at all and didn't realize it until later. I took a screenshot... Sorry I'm not folding for TR just now but I'll be back when I can put out better numbers.