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    SubjectRe: HZ, preferably as small as possible
    "Grover, Andrew" wrote:
    >
    > I'd like to see HZ closer to 100 than 1000, for CPU power reasons. Processor
    > power states like C3 may take 100 microseconds+ to enter/leave - time when
    > both the CPU isn't doing any work, but still drawing power as if it was. We
    > pop out of C3 whenever there is an interrupt, so reducing timer interrupts
    > is good from a power standpoint by amortizing the transition penalty over a
    > longer period of power savings.

    That makes a ton of sense.

    > But on the other hand, increasing HZ has perf/latency benefits, yes? Have
    > these been quantified?

    Not that I'm aware of. And I'd regard any such claims with some
    scepticism.

    > I'd either like to see a HZ that has balanced
    > power/performance, or could we perhaps detect we are on a system that cares
    > about power (aka a laptop) and tweak its value at runtime?

    It's all rather fishy.

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