RADV Lands Fast Clear Improvements, Helping RDNA With VKD3D-Proton

Samuel Pitoiset of Valve's Linux graphics driver team has been working on a number of improvements in recent days to the RADV Vulkan driver's handling around delta color compression (DCC) fast clears.

As noted yesterday there is now DCC MSAA fast clears for Navi 1 and Navi 2 RDNA GPUs among other fast clear improvements for benefiting these latest-generation Radeon GPUs.

That RADV fast clear activity has continued with more improvements landing today. Notably is now fast clears for concurrent images when comp-to-single is supported. This functionality is supported across GFX10/RDNA GPUs.

This is significant for helping to fix a performance gap between using concurrent and exclusive queues with VKD3D-Proton. In particular, the role playing game Scarlet Nexus that launched back in June is known to be helped by this latest patch. Additionally, the performance of DOOM Eternal is expected to be helped with the latest fast clears patch too.

AMD GPUOpen's RDNA performance guide is big on fast clear usage, "It cannot be overstated how much faster these clears are when compared to filling the full target...Fast clears are designed to be ~100x faster than normal clears."

It's great seeing Valve continuing to push all of these continued improvements to RADV even with it often outperforming AMD's own official closed-source Vulkan driver for Windows/Linux. These latest patches will be in next quarter's Mesa 21.3.