Intel Arc A580 idle power regression with kernel 7.0.14-20/22-pve

[seylon79]

Hi,

I've noticed what appears to be a kernel regression affecting the idle power consumption of an Intel Arc A580.

Hardware:

• Proxmox VE 9.2
• AMD Ryzen 5 9600X
• Intel Arc A580
• Arc is using the i915 driver

I originally noticed that the Arc was drawing significantly more power than expected at idle. I tested this by booting different installed Proxmox kernels.

Results:

Kernel	Arc A580 idle power
7.0.14-16-pve	~6 W
7.0.14-20-pve	~40–50 W
7.0.14-22-pve	~40–50 W

The difference is reproducible. I can boot 7.0.14-16-pve and the Arc returns to approximately 6 W idle. Booting 7.0.14-20-pve or 7.0.14-22-pve causes the idle consumption to increase substantially.

I also disabled GPU monitoring in Beszel (SKIP_GPU=true) during the testing, so the higher power draw isn't being caused by Beszel polling the GPU.

I verified the power difference using the i915 energy counter rather than relying only on monitoring software. On 7.0.14-22-pve, the counter increased by approximately 3.0 kJ in about one minute, corresponding to roughly 50 W.

Interestingly, I also noticed different behavior from the AMD iGPU between the kernels, although I haven't investigated that separately.

For now I've pinned the host back to 7.0.14-16-pve, where the Arc returns to its normal ~6 W idle consumption.

Is this a known regression in the newer 7.0 kernels, particularly around i915/DRM power management?

Thanks!

 

[dcsapak]

mhmm could you also check the -17, -18 and -19 kernels? this would shrink the possible regression window by a lot
from a good and a bad boot the following output would also be practical:

lspci -PP -vvv

 

[seylon79]

Thanks, I did some further testing to narrow this down.

I tested 7.0.14-17-pve first. The high idle power consumption was immediately present after boot, so I didn't test -18 or -19 since the regression is already present in -17.

I also tested the latest available kernel, 7.0.14-23-pve, to see whether the issue had been fixed there. Unfortunately the regression is still present.

My current results are:

Kernel	Arc A580 idle power
7.0.14-16-pve	~6 W
7.0.14-17-pve	~44 W
7.0.14-20-pve	~40–50 W
7.0.14-22-pve	~40–50 W
7.0.14-23-pve	~42 W

I also verified the -17 result using the i915 energy counter. Over approximately one minute it increased from 7,582,748,413 µJ to 10,209,383,605 µJ, corresponding to approximately 44 W.

After returning to 7.0.14-16-pve, the Arc immediately returned to its normal ~6 W idle consumption.

I've attached the requested lspci -PP -vvv output and diagnostics from the 7.0.14-17-pve boot.

So at this point the regression appears to be introduced somewhere between 7.0.14-16-pve and 7.0.14-17-pve, and it is still present in the current 7.0.14-23-pve.

Thanks!