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SubjectScheduling for heterogeneous computers

Are there plans for power-aware scheduling on heterogeneous computers that
processes & threads can opt-in to?

Several mainstream devices now offer power-aware heterogeneous scheduling:

* Lots of ARM (and therefore android) devices offer big.LITTLE cores.
* Apple's M1 CPU has "gold" and "silver" cores. The gold cores are faster
and have more cache. I think there are other microarchitectual
differences.
* Intel's Alder Lake CPUs have P and E cores. I'm told that the E cores
don't save power though since each core type still gets the same work
done per Watt, it's just that the P cores are bigger and faster.
* Multicore CPUs that offer frequency scaling could get some power savings
by switching off turbo boost and similar features. They wonThe work/watt
improves at the cost of throughput & responsiveness.

I'm aware that Linux does some Energy Aware Scheduling
https://docs.kernel.org/scheduler/sched-energy.html, however what I'm
looking for is an API that processes (but ideally threads) can opt in-to
(and out-of (unlike nice)) to say that the work they're currently doing is
bulk work. It needs to get done but it doesn't have a deadline and
therefore can be done on a smaller / more power efficient core. The idea is
that the same work gets done eventually, but for a background task (eg
Garbage Collection) it can be done in a greener or more
battery-charge-extending way.

MacOS has added an API for this as:
pthread_set_qos_class_self_np()
https://developer.apple.com/documentation/apple-silicon/tuning-your-code-s-performance-for-apple-silicon?preferredLanguage=occ

Windows has:
ThreadPowerThrottling
https://docs.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-setthreadinformation

I'm not aware of anything for Linux and I've been unable to find anything.
Are there any plans to implement this?

Cheers.


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