New kernel screws battery life. Suggested course of action?

MatthewScholefield

With the latest kernel upgrade from 5.2.20-130 to 5.3.8-133, my laptop's idle power usage went from 10W to 28W. I've set the default boot option to the old kernel, but will this eventually get booted off when there's another kernel update? Is it correct that the suggested thing to do is to attempt to send a bug to part of the Linux kernel mailing list or pray that it magically gets fixed in a future kernel version (a likely possibility)?

Just wondering what other people have done in this sort of situation on a rolling release distro.

Edit: Also, if anyone else has this issue and is curious, I think it could be related to this.

dbarron

Wait and see, it may be corrected in the next kernel.

RaMa

I use LTS kernel

MatthewScholefield

I just wanted to post a final update since it still happens with the latest kernel. Surprisingly, I tried another distro with a new kernel and it was fine.

Symptoms:

3x power usage
Properly throttled cpu hertz observed via watch grep \"cpu MHz\" /proc/cpuinfo

Failed solutions:

Kernel parameter intel_pstate=enable|disable|nohwp
Make Linux fast again
Disabling NVIDIA (If I have NVIDIA enabled my power usage is ~5-6x more)

Workarounds [that no longer work for me]:

Switching to older kernel that worked provided it still is an option
Switching to linux-lts, possibly adding nomodeset=1 if stuck with a blinking cursor

Anyways, somehow I lost the old kernel with the latest update. Since switching to lts causes intel xorg drivers to fail to load for me, I'll be leaving Solus for now 😢.

LukMas

I have the same symptoms on my working notebook. The good thing, for me, is that I barely move it away from the docking station, so it's not really a big problem. But, with the CPU throttling so much sometimes the system slows down and becomes almost unusable, for 10, 15 seconds.

I can live with this, but... But the truth is that:

LTS kernel now is unusable, at least for some notebooks
current kernel is also not the best solution, for some notebooks, because it makes them behave really weird

I cannot blame the developers for this, I know that they work hard to support Solus and they do for free. It just a pity that it's not so simple to have a fully working backup kernel to use up to when a new, fully working one, is released. But, I suppose that's the price to pay to have a rolling release. 😉

Note: on my personal notebook I have also noticed this, I just supposed that there's nothing to do because it's something related to the kernel, so the only solution is to "keep calm and carry on": I wait for the next kernel, hoping it will solve the problems.

MatthewScholefield

Just following up, I'm not sure if these things are all related but I will document my later findings not related to Solus:

After installing Manjaro and the 4.18 kernel, the high power usage problem persisted
I noticed after unplugging the power supply, the fans would die down and the power usage would remain normal. It appeared the problem was only when the AC was plugged in.
I noticed if I started psensor while the AC was plugged in, I would see a temp1 sensor that upon further inspection belonged to nouveau-pci-0100 even though I had no nvidia drivers installed (including nouveau. only intel xorg drivers). I noticed that as soon as I unplugged the power supply, the temp1 sensor stopped updating.
This led me to reading something mentioned the only way to disable the nvidia gpu was to install the nvidia drivers and disable it.
After I installed either the nvidia-prime or nvidia-bumblebee drivers in Manjaro it solved my problem. Supposedly this would also work just by installing the regular nvidia drivers and setting it to intel-only in nvidia-settings

TL;DR, for my specific problem, actually installing the nvidia drivers and then from there making sure it was set to intel solved my power usage problem. However, It's unclear whether this solution was a different problem with Manjaro or if it related to the initial problem with Solus.

Philbohackinz

A dedicated graphics card will drain your battery life pretty quick, even just surfing the web or doing video chat. Weather its nouveau or nvidia proprietary it it still using the graphics. But like you said being able to change to Intel will help slow the drain on your battery. I believe Kernel 5.4 had some additions to help with battery life.

I personally have added system76-power to Solus in Gnome. I find they have the best and easy to use tools for extending battery life or boosting performance in your laptop. They may even add auto cpufreq into it. I heard that is pretty good but I haven't messed around with it to get that working in Solus.

MatthewScholefield

Philbohackinz You might have missed what I wrote. I actually had neither nouveau nor nvidia drivers installed and it was rendering everything using the intel card. So not an it-is-what-it-is style situation but rather a strange-bug situation.

System76-power is an interesting mention. Wait, did you actually get it to change the graphics profile using system76-power in Solus or do you think it is only able to change the backlight? Reason I'm asking is because I assumed changing graphics modes would be very OS specific and only work in Pop!_OS

Philbohackinz

MatthewScholefield
Yes I must have misunderstood what you have said.
I did have it working or so I thought. Now I have some modprobe error. So I'll have to figure that out. I think it should I just need to troubleshoot.