kernel 6.6.58-r1 and amdgpu power draw

[krumpf]

Hi.
First, a bit on context. Lately, I'm playing Cyberpunk2077, game that is quite demanding on GPUs. I'm using vsync to limit fps output to 60, my gpu can go over 60 fps, but then the card gets power hungry, heats more, requires more cooling, and that's where the gpu fans can get very noisy. So limiting the fps also helps limiting the fan noise.

When using the kernel 6.6.52, mangohud shows me when playing the card draws around 200W (+/- 10%) in quite stable manner, it doesn't get very hot, and the fans do a slightly noise.
After upgrading to kernel 6.6.58-r1, with the very same game settings (and no patch changing anything in game), the power draw rises to 290-300W, card gets very hot, and fans go wild at max speed (and max noise).

So I'm wondering if there were changes in amdgpu driver between those two kernel versions, especially in the way it allows gpu to draw more power. Did anyone notice the same thing ? Are there any release notes that could explain that ?
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Dragon Princess Music Games Heroes and villains

[krumpf]

So, after searching on the web, installing sys-apps/lact, and searching the web even more, I found a solution in a reddit post.
As I understand it (I might be wrong), the amdgpu driver tries to overclock the gpu/vram until it reaches hardware limitations (either temperature or power limit). As the gpu hotspot temp can reach up to 115°C, it pushes the cooling fans to their max, and they become as noisy as a vacuum cleaner.
When setting the /sys/class/drm/card0/device/power_dpm_force_performance_level to "high", the driver is forced to keep gpu/vram clocks within specs, meaning no overclock, no extreme temperature (it keeps in the 80-90°C range), and fans just produce a background fan noise (audible but not annoying).
For now I'm using lact to switch the gpu performance level, just need to select "high" before gaming, and to set to "automatic" when doing desktop stuff. I'm still a bit puzzled from that driver behavior change between kernel 6.6.52 and .58, possible backports from the kernel mainline ? For now, guess I'll have to wait for next LTS kernel, hopefully 6.13 as it's supposed to bring a lot of changes to amdgpu driver.
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Dragon Princess Music Games Heroes and villains