Marek Olšák who had been a longtime AMD Linux driver engineer specializing in the RadeonSI Gallium3D driver, [1]recently began working for Valve on their Linux graphics driver team. His focus has understandably shifted to working on the RADV Vulkan driver and one of his early optimizations now with the Valve hat on is up to a 100% pixel throughput optimization for the RADV driver, which is already quite well optimized thanks to years of investment from Valve, Red Hat, and others.

A merge request opened by Marek last week for Mesa's RADV driver is to increase the pixel throughput within the sample_mask_in code. The impact is very pronounced:

"This increases pixel throughput with sample_mask_in for RADV:

- by up to 100% for 32bpp if the number of PS input VGPRs changes from 3 to 2, and

- by up to 50% for <= 64bpp when the number of PS input VGPRs changes from 5 to 4"

No real world benchmark/performance impact numbers were cited, just the benefit to the pixel throughput.

As of today [2]the merge request is now merged for Mesa 26.2.

It will be interesting to see what other sort of optimizations Marek will be able to cook up at Valve for RADV thanks to his many years working on the Radeon Gallium3D code.



[1] https://www.phoronix.com/news/AMD-Marek-Joins-Valve

[2] https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/41768