Can I get Dolphin devs' opinion on this?

[DaRkL3AD3R]

https://www.youtube.com/watch?v=e5dWy5a0vqI

This is a video I made to demonstrate something rather frustrating that's happening with the Nvidia GLCache and OpenGL applications, including Dolphin.

TLDW - when the GLCache is empty, stutters will occur. The GLCache empties on its own after a set amount of time or whenever you launch a different OpenGL or Vulkan application, effectively wiping out the old shader cache and producing stutters.

I'm almost positive this is solely a case of the Nvidia driver being really freaking dumb, but is there anything developers can do to work around this? Is there any developer control over the shader cache ID that Nvidia uses so we can at least get separate folders and files between various OpenGL/Vulkan applications?

[degasus]

There is shader compilation and shader variants compilation. The former is exposed to the application and both dolphin and cemu caches those shaders. The later isn't exposed to the application and so only the driver is able to cache them. Worse, there is no reflection if the next draw call needs a new shader variant, so there isn't a way to use some ubershader while compiling the shader variant.

Good luck, in Vulkan, you can also cache shader + pipeline object. As the variants depend on other states within the pipeline object, this will implicitly also caches the shader variants. That's why we suggest to use Vulkan or D3D over OpenGL on nvidia if you want to avoid stutter.

[DaRkL3AD3R]

Degasus and Stenzek, can you guys test this for me? Go to the following Nvidia thread and pull the Nvidia Inspector custom setting that Guzz posted: https://forums.geforce.com/default/topic/1020898/geforce-drivers/why-does-shader-cache-option-do-absolutely-nothing-in-driver-profiles-/?offset=16#5202276



I am getting flawless gameplay now on CEMU using this setting (OGLShaderCache set to Off in Nvidia Inspector) because it is allowing the application to assume full control over the shader cache. I tested it on Dolphin in Vulkan using Hybrid ubershaders and noticed a marked improvement in stutter reduction. I think this is it guys. I think we have the answer to the Nvidia question.


I spoke too soon. The stupid Nvidia driver is still latching on to shaders and handling its own cache. With the option above, all it does is keep it in RAM until the application closes, and where it would usually write to disk, it prevents that from happening. But the stutters are still there. I'm really pissed about it too because this genuinely felt like the fix. A toggle to tell the driver to screw off and stop interfering with OpenGL and Vulkan shader caches. It's a shame it didn't pull fully through. This would have been such a nice fix.