[Question] Disable CPU cores to prolongate battery time based on the config file about auto-cpufreq

[AdnanHodzic]

Sounds like a good idea for settings file idea in #26. Something like this: limit number of cores (available cores: xy)

[mmstick]

I have doubts that disabling CPU cores would improve battery life. I suspect this would decrease battery life, because you need to do the same amount of work either way, and forcing work onto fewer processors just keeps the fewer cores operating at higher frequencies for longer periods of time. Efficiency tends to reduce at higher frequencies.

[Red-Eyed]

@mmstick yep, you a right. But what if to disable/enable cores depending on the average CPU load % ?
So, if my laptop is on IDLE, than maybe disabling CPU cores will decrease power consumption?

[AdnanHodzic]

The more I'm thinking about this, this shouldn't be part of the settings file, as it will definitely have counter effects as @mmstick pointed out. But I'm sure if load/cpu usage is very low and cores are dropped it'll only increase battery life. Real life example, certain cars (i,e: BMW) are doing this where at low speeds/eco boost mode they only use 1 cylinder to use as little fuel as possible.

Hence we should go in direction of handling this automatically. Where if absolutely minimum load/cpu usage is detected to proceed with disabling the cores. Then with slightness change in cpu/load to enable cores. @Red-Eyed I think we should only make these changes while in powersave.

[Red-Eyed]

I think that internal combustion engine(ICE) is a bad analogy as CPU and ICE has different nature, so it needs to be investigated and tested firstly.

Yes, sure in powersave only.

[AdnanHodzic]

I think that internal combustion engine(ICE) is a bad analogy as CPU and ICE has different nature

Agreed, I realized the same as soon as I posted it :)

so it needs to be investigated and tested firstly.

Of course, research and testing is what's it's all about.

Yes, sure in powersave only.

👍

[LadislavMalecek]

I have lightly experimented with disabling CPU cores using cpufreq, and in my case, it increases battery life substantially. On Ryzen 5800h going from 16 threads to 4 increases the battery life from 7.5h to 9.5h while doing very light work/reading and from 4:20 to 5:20h while watching youtube. But more exact testing is needed.

[AdnanHodzic]

With v1.7.0 release it's now possible to manually define some of the settings instead of leaving everything to be picked up automatically. Could you try tweaking some of the available options and report back on how that worked for you?

Considering #26 is now also closed, I'll close this issue as well. Please re-open it if the problem persists.

[123batman]

@LadislavMalecek Can you please post your configuration on how to disable cores automatically? Are you using cpufreq and auto-cpufreq in parallel or how does it work?