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Re:PowerTOP – diagnose issues with power consumption and pow... by yewenjie on Sunday July 04, 2021 @01:11AM (#27727386)
Is it possible to get better than Windows power management with this tool? How?
Re:PowerTOP – diagnose issues with power consumption and pow... by yaantc on Sunday July 04, 2021 @02:04AM (#27727567)
I'd recommend just installing the "tlp" package, it includes most of what PowerTOP does and is "install and forget".

Just an anecdote: I'm using Linux on a professional laptop, the same most of my colleagues use with Windows 10 (Latitude 7490). My battery life is significantly higher, high enough that I never care really, and the laptop is quieter: hearing the fan is the exception, not the norm.

All this with Debian and the TLP package installed. The TLP configuration is just tweaked to aggressively idle the SSD (no spin down / spin up issue anymore) but that's it. I did this a long time ago when I moved from HDD to SSD, and just carry this over.

A good deal of the difference may come from the antivirus on Windows, but TBC.

Re:PowerTOP – diagnose issues with power consumption and pow... by quijoteuniv on Sunday July 04, 2021 @03:24AM (#27727889)
I have a low end HP because i needed a windows machine for some studies. The thing goes straight into fans on windows, when running on ubuntu almost never. Only when rebooting from windows to ubuntu and needs cooling down. There is only one explanation for that.
Re:PowerTOP – diagnose issues with power consumption and pow... by chrismorgan on Sunday July 04, 2021 @09:04AM (#27729327)
I recently got my new ASUS GA503QM (AMD Ryzen 5800HS) able to consume less power than Windows, but adjusting the CPU’s limits¹ and changing the scaling governor² did much more for obtaining protracted battery life than PowerTOP did.

I even discovered that if limit the CPU to an small enough value (e.g. 0.1W, not that it’s actually capable of going that low), it reduces the clock speeds to 400MHz (compared to its usual baseline of 1.2GHz, which is still the baseline even when limited to 5W). The system certainly feels much slower with all cores at 400MHz than it does with all cores at 4GHz! But still quite usable in general.

¹ e.g. `ryzenadj -a 5000 -b 5000 -c 5000` for roughly a 5W TDP.

² From schedutil to powersave: `echo powersave | sudo tee /sys/devices/system/cpu/cpufreq/policy*/scaling_governor >/dev/null`

Re:PowerTOP – diagnose issues with power consumption and pow... by darkfirefly on Sunday July 04, 2021 @10:05AM (#27729708)
Alternatively, I used zenstates and played around with VID values on different p-states (or is it c-states? I can't remember) which allowed my cores to go from ~400Mhz and then speed up as necessary.

There's info scattered around on the internet for how to do this; I don't have my script to do this easily accessible atm.

I do concur on the governor's though, nothing else really makes much of a different. My old HP laptop I permanently had on the powersave scheder and it would draw about 2.5W - the battery life was stupidly ridiculous. My new AMD Lenovo I can't even get below 6W by the same method unfortunately.

Re:PowerTOP – diagnose issues with power consumption and pow... by chrismorgan on Sunday July 04, 2021 @11:22AM (#27730331)
I haven’t compared power consumption for a full cycle of active use at 400MHz flat and 1.2GHz flat. I should try it. But as to whether it’s worth reducing the idle frequency, I doubt it: I observe no measurable difference between the two frequencies at idle—though it’s made harder by the fact that the /sys/class/power_supply/BAT0/power_now figure seems to take some time, even minutes, to reach a steady point, e.g. slowly drifting down from 7W to 6.6W. And the lowest it’ll reach seems to vary a lot, e.g. sometimes it won’t drop below 6.6W, and other times it’ll settle to 6.1W, about the lowest I’ve measured. But at 400MHz flat it can’t quite get it to 9W with a dozen or so `while True: pass` busy loops in Python, while at 5W (1.2GHz) I can get it up to almost 11.5W. (And then I throw it into boost mode and watch it climb rapidly to 64W while remaining dead silent, and wonder why the fan isn’t roaring away as it’s supposed to in boost mode and what of my fiddling just now prevented it from doing its job.) Even these comparisons aren’t great because of the lack of GPU load. Wonder if I can throttle that at all?
Re:PowerTOP – diagnose issues with power consumption and pow... by hbogert on Sunday July 04, 2021 @02:10AM (#27727591)
Not sure if better. But the biggest change in my case was not all the changes suggested by powertop, but probably kernel changes.went from 8-9w idle, to 5-6w. Over the course of 2 years wit a Lenovo t480s. I think that 5-6w is slightly better than windows.
Re:PowerTOP – diagnose issues with power consumption and pow... by raegis on Sunday July 04, 2021 @03:54AM (#27727996)
I get less than 5W idle on my T480 using TLP running on Debian Bullseye. Didn't have to config anything. But still it's only 8 hours.
Re:PowerTOP – diagnose issues with power consumption and pow... by hbogert on Sunday July 04, 2021 @08:35AM (#27729185)
your battery is probably being worn out. Mine's already under 80% of the design capacity. So more or less, tlp and kernel optimization has only negated the decline of my battery :/
Re:PowerTOP – diagnose issues with power consumption and pow... by raegis on Thursday July 08, 2021 @10:09PM (#27779791)
Can you explain this, or provide a reference?
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Re:PowerTOP – diagnose issues with power consumption and pow... by na85 on Sunday July 04, 2021 @01:24AM (#27727429)
It's an operating system. https://www.microsoft.com/en-ca/windows
Re:PowerTOP – diagnose issues with power consumption and pow... by nindalf on Sunday July 04, 2021 @02:04AM (#27727564)
Better to flag bad faith comments rather than reply in earnest.
Re:PowerTOP – diagnose issues with power consumption and pow... by nixpulvis on Sunday July 04, 2021 @02:19AM (#27727625)
Not bad faith, just bad form.

I was probing for an explanation as to how Windows worked that needs beating by use of powertop. Power management is a wholistic concept for a computer.

I appreciate that the comment was probably more along the lines of "how can I find slow processes on Windows" or something else that powertop may be useful for here.