The latest Mesa Radeon Vulkan (RADV) driver substantially improves ray-tracing performance on RDNA 2 and RDNA 3 GPUs. By implementing support for batch acceleration builds, ray-tracing performance is as much as 3x faster. The merge request allows for a bulk BVH queue that is accumulated and dispatched as late as possible. This helps improve ray-tracing performance in titles without native batching support.
This converts radv_CmdBuildAccelerationStructuresKHR to a simple shim that pushes the actual build commands to a queue, where they are accumulated and dispatched as late as possible.
This helps especially with games that don’t do any build command batching of their own. For example, it triples the performance of Hitman 3.
Hitman 3 sees the biggest uplift in performance, a 3x gain over the existing release. Lego Builders is up to 2x faster with the patch. Control, Minecraft, and other GeForce RTX partner titles also see a single to double-digit increase in ray-tracing performance.
“the perf uplift from this PR is huge in a few games, out of the ones I own lego builders journey gets a 2x improvement in performance. Control gets an additional ~5 fps at 1080p, Minecraft RTX (education edition) gets ~10 fps more. When paired with the monolithic pipeline MR it completely blows amdvlk out of water.
Tested on my rx6800.”
These optimizations should be expected with Mesa’s next quarter 23.3 release, so don’t expect any immediate gains.