AMD Radeon "SISCHED" Support Has Been Retired

Not many AMD Radeon Linux gamers have been using the "sisched" SI machine instruction scheduler in recent times. This non-default scheduler hasn't been well maintained. Additionally, when on the RADV Vulkan driver, using the Valve-backed compiler back-end has been far superior. As such, SISCHED has now been gutted out of Mesa.

SISCHED being retired is of little surprise. Last month we outlined that the Radeon sisched scheduler is obsolete. While it was very promising at first, it hasn't received much attention in many months while the likes of ACO have shown much more potential.

The SISCHED lead developer also commented in the forums, "My mistake was probably to decline requesting llvm push accesses soon after sisched was merged. Ever since the merge it has been an uphill battle to get the slightest patch merged. My patches took months, years or even infinite time to get reviewed and pushed. It's been two years now i gave up and just wish it was dropped."

As of this weekend, it's been dropped. AMD developer Pierre-Eric Pelloux-Prayer wiped out the integration on the Mesa side in 20.1-devel on the basis of it not being maintained anymore.

ACO hasn't been ported (yet) to the RadeonSI Gallium3D driver at all for juicing more performance out of the GPU, but even the out-of-the-box RadeonSI OpenGL performance is still better off now than it was back during the SISCHED triumphant days.