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    SubjectRe: dynamic-hz
    Hi!

    > > > The performance benefit, if any, is often lost in noise during
    > > > benchmarks and when there, is less than 1%. So I was wondering if you
    > > > had some specific advantage in mind for this patch? Is there some
    > > > arch-specific advantage? I can certainly envision disadvantages to lower Hz.
    > >
    > > There are apparently some laptops which exhibit appreciable latency between
    > > the start of ACPI sleep and actually consuming less power. The 1ms wakeup
    > > frequency will shorten battery life on these machines significantly. (I
    > > forget the exact numbers - Len will know).
    >
    > Is there any recommended lower bound setting?
    > Would there be a point in recommending lower settings for desktops
    > running only text consoles opposed to X desktops?

    I tried defining HZ to 10 once, and there are some #if arrays in the
    kernel that prevented me from doing that.

    Some drivers do timeouts based on jiffies; having HZ=1 may turn 20msec
    timeout into 1sec, that could hurt a lot in the error case...

    Pavel
    --
    People were complaining that M$ turns users into beta-testers...
    ...jr ghea gurz vagb qrirybcref, naq gurl frrz gb yvxr vg gung jnl!
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