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Indeed, and there's a thing called "race to sleep". That is, you want to light up as much of the core as possible as fast as possible so you can get the CPU back to idle as soon as possible to save on battery power, because having the CPU active for more time (but not using as many circuits as it "could") draws a lot more power.




At the same time, it takes a certain amount of time for a CPU to switch power levels, and I remember it being surprisingly slow on some (older?) processors.

So in Linux (and I assume elsewhere) there were attempts to figure out if the cost in time/power to move up to a higher power state would be worth the faster processing, or if staying lower power but slower would end up using less power because it was a short task.

I think the last chips I remember seeing numbers for were some of the older Apple M-series chips, and they were lightning fast to switch power levels. That would certainly make it easier to figure out if it was worth going up to a higher power state, if I’m remembering correctly.


I deliberately put my govenor to the conservative one, as I hated fans spinning up for a second and then down again repeatedly. Much rather sacrifice a bit of battery and speed for quiet.

Can't you just cap the fan speed? Or does it actually get too hot at a lower fan speed to where it would throttle or crash?

It's just bad fan curve for given workload. Sharp rises and drops are annoying to hear, curve that does that + race-to-sleep do not work together. Low speeds do cause throttling.

I wanted the full power when doing long compiles and such. Just not the fan jojo acion when neowsing the web or writing.

Also swapping the governor was trivial and reliable. Modifying fan profiles has always been a bit of a struggle for me, with huge differences in hardware support, persistence etc.


> jojo acion when neowsing

jumping into action when browsing


Thanks. I hate the autocorrect as it's so often wrong, but hitting the right "keys" with no tactile feedback is such a pain. I miss T9...

Smart. That would drive me nuts too.



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