RADV Optimized By Valve For An Upcoming Game - Nearly Matching The Windows Performance

Valve's Linux graphics driver developers continue relentlessly optimizing the Mesa Radeon Vulkan driver "RADV" and today landed an optimization for an unnamed, upcoming game where now it's able to nearly match the performance enjoyed under Windows.

Prolific Mesa developer Samuel Pitoiset at Valve, who joined back in 2016 after starting out as a GSoC Nouveau developer, landed a patch to wait for occlusion queries in the resolve query shader. Pitoiset explained in the patch message:

"This is really noticeable for games that resolve a bunch of occlusion queries (in this case 4096) because it seems that emitting 4096 WAIT_REG_MEM packets can stall more than expected. Fixes this by waiting for queries in the resolve query shader."

But what makes this performance optimization all the more interesting is the next part:

"This improves performance of an unreleased game by +~10% (71->78 FPS). RADV should now be really close to Windows performance for that title."

There's no mention or hints of what that unreleased game is, but it should be some notable title given it's already being tuned in advance by Valve's Linux / Steam Play team. It does appear to be in the context though of a Windows game on Linux via Steam Play as the MR mentions, "This removes the bubble with occlusion queries reported by Hans-Kristian and gives +~10% FPS in that game." Hans-Kristian Arntzen is the lead developer on VKD3D-Proton for implementing Direct3D 12 on Vulkan for Proton / Steam Play.

In any case, great job by Valve's Linux team and will be interesting to see what is that unreleased game now delivering "really close" to the Windows performance.