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    SubjectRe: [BUG nohz]: wrong user and system time accounting
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    On Thu, 2017-03-30 at 09:02 -0400, Rik van Riel wrote:
    > On Thu, 2017-03-30 at 14:51 +0200, Frederic Weisbecker wrote:

    > > Also, why does it raise power consumption issues?
    >
    > On a system without either nohz_full or nohz idle
    > mode, skewed ticks result in CPU cores waking up
    > at different times, and keeping an idle system
    > consuming power for more time than it would if all
    > the ticks happened simultaneously.

    And if your server farm is mostly idle, that power savings may delay
    your bankruptcy proceedings by a whole microsecond ;-)

    Or more seriously, what skew does do on boxen of size X today is
    something for perf to say. At the time, removal was very bad for my 8
    socket box, and allegedly caused huge SGI beasts in horrific pain.

    -Mike

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