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    SubjectRe: Why HZ on i386 is 100 ?
    >>>>> On Sun, 21 Apr 2002 18:00:22 +0000, Pavel Machek <pavel@suse.cz> said:

    Pavel> .5% still looks like a lot to me. Good compiler optimization
    Pavel> is .5% on average...

    Umh, but those optimizations are interesting only if they're
    cumulative, i.e., once you've got 10 of them and they make a *total*
    difference of 5% (actually, I'm doubtful anyone really notices
    differences of 20-30% other than for benchmarking purposes... ;-).

    For me, 1% is the magic threshold. If we find real apps that get a
    higher penalty than that, I'd either lower the HZ or see if we can
    tune the timer tick to be within a safe margin.

    No matter what, though, higher tick rate clearly incurs somewhat
    higher overhead. The benefit is lower application-level response time
    and finer-granularity timeouts. I assume Robert has all the
    benchmarks to show that. ;-)

    --david
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