WaitForPresentFeb 10
Is there anything like Dx12 SetStablePowerMode available on linux?
Show threadJosh SimmonsFeb 10

@WaitForPresent on which hardware? I'm not sure if there's a useful cross-vendor API hooked up anywhere but getting stable clocks on amd is a matter of writing some values to some files.

https://docs.kernel.org/gpu/amdgpu/thermal.html profile_peak / profile_standard here for amdgpu.

GPU Power/Thermal Controls and Monitoring — The Linux Kernel documentation

Show threadPhilip TrettnerFeb 10

@dotstdy @WaitForPresent I got `echo performance | sudo tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor` for that (works on the intel/amd I use)

EDIT: apparently this needs cpufreq kernel stuff and might not work reliably, but at least it's a term to look up

EDIT2: this is _CPU_, not _GPU_, my bad

Show threadJosh SimmonsFeb 10
@artificialmind @WaitForPresent that's CPU scaling rather than GPU, and setting the governor itself is not exactly sufficient anymore.
Show threadPhilip TrettnerFeb 10
@dotstdy @WaitForPresent Oh wow missing some coffee here, totally misread that, sorry!
Show threadJosh Simmons
@artificialmind @WaitForPresent no biggie, there's also "game mode" which sets a bunch of these tunables automatically. But not useful for profiling alas.
Feb 10 at 12:54pmPhanpy
Show threadPhilip TrettnerFeb 10
@dotstdy @WaitForPresent Ok but I found similar knobs for NVidia in nvidia-smi: https://docs.nvidia.com/deploy/nvidia-smi/index.html (-lgc and -lmc are for locking clock rates). Global, requires root, requires specific values, BUT might make for a better benchmarking experience anyways.
Show threadJosh SimmonsFeb 10
@artificialmind @WaitForPresent one more thing, if you use something like VK_KHR_performance_query, on amd hardware that will put your GPU into profile clocks. Idk if there's an extension I'm missing which lets you specify it directly.
Show threadWaitForPresentFeb 10
@dotstdy @artificialmind Yeah that does not seem to be a thing (the VK_KHR_performance_query part) on the proprietary Nvidia driver at least.
Show threadslembckeFeb 10
@dotstdy @artificialmind @WaitForPresent Oh? I’ve been using it for exactly that as it seems to remove most of the variance in my runtimes. >_> what’s missing in it?
Show threadJosh SimmonsFeb 10
@slembcke @artificialmind @WaitForPresent it doesn't lock your clock speed, it just enables the "performance" governor. For reproducible numbers you likely want to disable boost as well, for example. Plus it won't put your GPU into fixed clock configuration.