RADV Adding New Bit To Help Avoid Stuttering With DXVK

The RADV Vulkan driver will soon have VK_PIPELINE_CREATE_DISABLE_OPTIMIZATION_BIT to help avoid stuttering with DXVK for running Direct3D 11 games on Wine over Vulkan.

While DXVK performance is already quite compelling and handling a surprising number of D3D11 games rendered via Vulkan considering how young this project is, DXVK and potentially the other Vulkan Linux drivers may soon see less stuttering.

DXVK has an in-development branch called disable-opt-bit. That branch is making use of Vulkan's VK_PIPELINE_CREATE_DISABLE_OPTIMIZATION_BIT on supported drivers to reduce compile times. In turn, they hope that will reduce stuttering during game-play caused by the Vulkan compilation process.

VK_PIPELINE_CREATE_DISABLE_OPTIMIZATION_BIT enforces that the created pipeline is not optimized, which means that the pipeline may not be as fast, but the compile time should be quicker. This doesn't mean though that DXVK will run slower, but rather while using this disable optimization flag, DXVK will still fire off an optimized pipeline compilation but done asynchronously. Once that optimized compilation is done, it will be swapped in to replace the unoptimized build. This should lead to a better in-game experience for DXVK.

Thanks to Valve's Timothy Arceri, there is a patch pending to support the disable optimization bit. In Arceri's testing, he found the compilation speed to be about 10% faster.

Now hopefully the NVIDIA Vulkan driver and others will also support VK_PIPELINE_CREATE_DISABLE_OPTIMIZATION_BIT.