AMD's RadeonSI/Gallium3D Linux Graphics Driver Gets Optimized For Ryzen CPUs
It's arguably a bit late, but patches are now pending for optimizing the RadeonSI Gallium3D open-source Linux graphics driver for the AMD Ryzen CPU microarchitecture.
What this set of patches do to the Mesa Gallium3D and RadeonSI driver code is optimize it for the AMD Zen architecture with its multiple core complexes (CCX). The new code allows for the pinning of the application thread and driver execution threads to the same CCX where they are able to share the same L3 cache.
By ensuring all of the driver threads for a given application/game are pinned to the same L3 cache / CCX as the application, there can be a significant performance benefit. In OpenGL micro-benchmarks there was an increase in performance by 32% for a draw elements operation or 25% for DrawArrays when using an AMD Ryzen Zen 1 CPU.
For real-world games/benchmarks, the performance benefit is expected to be much less than those micro-benchmarks but still should be noticeable. I'll be firing up some benchmarks in the next few days with these Mesa patches.
For now the patches are under review but will hopefully be mainlined for Mesa 18.3-dev in short order. Stay tuned for the benchmarks on these RadeonSI+Ryzen optimizations.
What this set of patches do to the Mesa Gallium3D and RadeonSI driver code is optimize it for the AMD Zen architecture with its multiple core complexes (CCX). The new code allows for the pinning of the application thread and driver execution threads to the same CCX where they are able to share the same L3 cache.
By ensuring all of the driver threads for a given application/game are pinned to the same L3 cache / CCX as the application, there can be a significant performance benefit. In OpenGL micro-benchmarks there was an increase in performance by 32% for a draw elements operation or 25% for DrawArrays when using an AMD Ryzen Zen 1 CPU.
For real-world games/benchmarks, the performance benefit is expected to be much less than those micro-benchmarks but still should be noticeable. I'll be firing up some benchmarks in the next few days with these Mesa patches.
For now the patches are under review but will hopefully be mainlined for Mesa 18.3-dev in short order. Stay tuned for the benchmarks on these RadeonSI+Ryzen optimizations.
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