Forum Discussion
DX11 related lag
Lately I have run into a really big problem. Stomach churning, throw the rift off my head, reach for a bucket, awful lag and it has nothing to do with the frame rate. There is no choppyness associa...
I figured out the issue!
It appears to be a Unity bug with DX11. Essentially QualitySettings.maxQueuedFrames is not working with DX11. It doesn't matter what you set it to, the latency result is always the same. I filed a bug on Unity to see if they can fix it.
Fortunately there is a workaround (at least for Nvidia cards). I have an Nvidia GTX 760 and in the driver there is a setting that overrides application max queued frames setting.
I ran some tests with my latency tester just to verify what my eyes and brain were telling me, and it is pretty clear this setting fixes the issue and shows that QualitySettings.maxQueuedFrames is not functional in DX11 (seems to work fine in DX9).
Attached is a picture showing where the override setting is in the Nvidia driver.
NvidiaMaxPreRenderedFrames.png
ccs
It appears to be a Unity bug with DX11. Essentially QualitySettings.maxQueuedFrames is not working with DX11. It doesn't matter what you set it to, the latency result is always the same. I filed a bug on Unity to see if they can fix it.
Fortunately there is a workaround (at least for Nvidia cards). I have an Nvidia GTX 760 and in the driver there is a setting that overrides application max queued frames setting.
I ran some tests with my latency tester just to verify what my eyes and brain were telling me, and it is pretty clear this setting fixes the issue and shows that QualitySettings.maxQueuedFrames is not functional in DX11 (seems to work fine in DX9).
Application Nvidia driver max frames QualitySettings. latency latency latency avg
maxQueuedFrames low high 10 runs
vsync off Use the 3D application setting 0 9 44 21.3
vsync off Use the 3D application setting 5 10 49 24.9
vsync off 1 0 11 34 19.8
vsync on Use the 3D application setting 0 18 79 53.6
vsync on Use the 3D application setting 5 16 71 41.1
vsync on 1 0 9 32 16.2
Attached is a picture showing where the override setting is in the Nvidia driver.
NvidiaMaxPreRenderedFrames.png
ccs
