RADV Driver Lands Another Optimization: "Missing In RADV For A Very Long Time"
([Mesa] 38 Minutes Ago
RADV)
- Reference: 0001619872
- News link: https://www.phoronix.com/news/Mesa-26.1-RADV-Four-Year-Opt
- Source link:
A four year old optimization idea for the RADV driver was scratched off the TODO list last week for next quarter's Mesa 26.1 release.
Opened back in May 2022 was [1]this ticket by Timur Kristof of Valve's Linux graphics team:
"radv: Port si_emit_guardband to RADV
Setting PA_SU_HARDWARE_SCREEN_OFFSET properly (like RadeonSI does) should improve clipping (not culling) performance."
After no major work on it until a week ago, Samuel Pitoiset -- also of Valve's Linux graphics team -- has ported the optimization over to the RADV Vulkan driver.
[2]This code was merged last week for Mesa 26.1 RADV to optimize the clipping performance with PA_SU_HARDWARE_SCREEN_OFFSET.
The PA_SU_HARDWARE_SCREEN_OFFSET register has been found on AMD GPUs for at least 16+ years and making use of it should help with clipping performance. No specific performance numbers were shared though as part of either the issue tracker or merge request.
[1] https://gitlab.freedesktop.org/mesa/mesa/-/issues/6492
[2] https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/40249
Opened back in May 2022 was [1]this ticket by Timur Kristof of Valve's Linux graphics team:
"radv: Port si_emit_guardband to RADV
Setting PA_SU_HARDWARE_SCREEN_OFFSET properly (like RadeonSI does) should improve clipping (not culling) performance."
After no major work on it until a week ago, Samuel Pitoiset -- also of Valve's Linux graphics team -- has ported the optimization over to the RADV Vulkan driver.
[2]This code was merged last week for Mesa 26.1 RADV to optimize the clipping performance with PA_SU_HARDWARE_SCREEN_OFFSET.
The PA_SU_HARDWARE_SCREEN_OFFSET register has been found on AMD GPUs for at least 16+ years and making use of it should help with clipping performance. No specific performance numbers were shared though as part of either the issue tracker or merge request.
[1] https://gitlab.freedesktop.org/mesa/mesa/-/issues/6492
[2] https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/40249