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Comment by fooctrl | Hacker News Reader

auto-cpufreq author here, I'm here if you have any questions!

You should be clearer what this actually does.

All mainstream CPUs and operating systems are dynamically adjusting frequency and other internal behavior to optimize power versus other factors. Some of these adjustment are done in hardware (i.e., intel_pstate aka "speed shift" aka HWP) which is both faster than software and can use internal metrics not available to software.

So you can't just say you're adjusting frequency dynamically to be optimal: something like that (or an attempt, at least) already happens. So what does this tool really do?

Are you talking about adjustments in hardware by drivers which can't even detect if my laptop is not connected to power source anymore and continue running on maximum frequency?

Please take a look at the auto-cpufreq demo video I made which should clear some things out: https://www.youtube.com/watch?v=QkYRpVEEIlg

It's old and many things have been improved and added since then, but it describes the essence.

You can also refer to blog post on what prompted me to make one such tool: https://foolcontrol.org/?p=3124

> Are you talking about adjustments in hardware by drivers which can't even detect if my laptop is not connected to power source anymore and continue running on maximum frequency?

I am talking about hardware power control in general. I wouldn't expect hardware power control itself to make different decisions based on plugged-in or not: that's a decision delegated to the user via the OS. HWP only implements low-level control based on the parameters set by something higher up.

I don't know if I'll watch the video, but you should make clear in your README what this tool actually does. Saying that it adjusts frequency dynamically isn't very useful. Telling people to disable `intel_pstate` without further comment is extremely suspect since then you're giving up HWP at an unknown cost.

If this simply adjusts the power governor when the laptop is plugged/unplugged, just say that!

Would you considered using intel_pstate=passive, and then use x86_energy_perf_policy/cpupower to turn the knobs on how to influence the governor? This'll let the CPU do its lower latency internal frequency changing. But of course, its not a one-size-fits-all approach for AMD/ARM.

On my Alienware AMD laptop, lm- sensors detects nothing. Do you think your program would help me on it? It doesn't support Linux but I'm running Ubuntu on it anyway. I have issues with screen brightness, fan speed, and battery life. Otherwise works great.

Best way to find out if it'll help you is to try it out! It has 2 modes, "monitor" which help you evaluate what it would do for you without making any actual changes.

If you like what it suggest you can run it in "live" mode, which will make the suggested changes. But after you stop "live" mode after reboot all settings will go back to defaults.

If you're happy with results then and want to run it in background all the time proceed with "install".

Reference: https://github.com/AdnanHodzic/auto-cpufreq/#how-to-run-auto...

Also I suggest you watch auto-cpufreq demo Youtube video which explains it all: https://www.youtube.com/watch?v=QkYRpVEEIlg

I tried it out. It doesn't get temps, as I expected. But it does switch down into power save mode on battery and switch back to performance on AC. Battery life has improved by over 50% from 4h to over 6h. Thanks for making this!

Thanks, I will give it a try!

How do the the latest Intel and AMD CPU's compare in how they handle speed and power usage with regards to the main stand-out differences between the two?

Sorry, but can't nswer that since all hardware I have is powered by Intel. Maybe it would be a good idea to ask this same question on: https://github.com/AdnanHodzic/auto-cpufreq/discussions

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