Linux developer Lionel Landwerlin is a graphics driver engineer who identified a bit of missing code in the open-source Intel Arc driver. The Intel Vulkan RT code change was only one line of code but he claims it provides “Like a 100x (not joking) improvement.“
It’s a simple oversight from when that code was originally written but means a massive performance improvement due to that lapse. At least it was caught now and prior to Intel Arc Graphics appearing with the masses. With Mesa 22.2 due to be branched in the coming days, Mesa 22.2 with this RT fix/optimization and plenty of other open-source Intel Linux graphics driver improvements will be out as stable around the end of August.
Intel has been working on their Vulkan ray-tracing support going back to late 2020 in preparation for Xe HPG introducing hardware RT capabilities.
The Linux developer explained that the missing code had to do with memory allocation for Vulkan ray-tracing. A flag had not been set which was said to prevent scratch memory buffers from residing on the local GPU memory.
New driver updates from Intel are anticipated following the recent launch of the Intel Arc A380 in China and the expected global release of the Intel Arc A750 Limited Edition graphics card sometime this summer. It is possible that Intel could implement this fix in a future driver update.