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    SubjectRe: [PATCH] Optimize int_sqrt for small values for faster idle
    On Mon, Feb 01, 2016 at 10:25:17PM +0100, Rasmus Villemoes wrote:
    > On Thu, Jan 28 2016, Andi Kleen <andi@firstfloor.org> wrote:
    >
    > > From: Andi Kleen <ak@linux.intel.com>
    > >
    > > The menu cpuidle governor does at least two int_sqrt() each time
    > > we go into idle in get_typical_interval to compute stddev
    > >
    > > int_sqrts take 100-120 cycles each. Short idle latency is important
    > > for many workloads.
    > >
    >
    > If you want to optimize get_typical_interval(), why not just take the
    > square root out of the equation (literally)?
    >
    > Something like

    Looks good. Yes that's a better fix.

    -Andi

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