Linux Kernel 4.17 Offers Some Promising Power-Savings Improvements
The most promising power management change in Linux 4.17 is a rework of the kernel's idle loop that may lead to some systems seeing their power drop by up to 10%+.
Intel's Rafael Wysocki who also serves as the Linux PM/ACPI subsystem maintainer explained of the change, "the rework of the idle loop in order to prevent CPUs from spending too much time in shallow idle states. It reduces idle power on some systems by 10% or more and may improve performance of workloads in which the idle loop overhead matters... Making it stop the scheduler tick before putting the CPU into an idle state only if the idle duration predicted by the idle governor is long enough. That required the code to be reordered to invoke the idle governor before stopping the tick, among other things."
|Linux 4.17 Offers Some Promising Power-Savings Improvements - Phoronix
Phoronix is the leading technology website for Linux hardware reviews, open-source news, Linux benchmarks, open-source benchmarks, and computer hardware tests.