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    SubjectRe: web page on O(1) scheduler
    At 08:38 PM 5/21/2003 -0400, Rik van Riel wrote:
    >On Wed, 21 May 2003, Mike Galbraith wrote:
    > > At 11:49 PM 5/20/2003 -0700, David Mosberger wrote:
    > > >Recently, I started to look into some odd performance behaviors of the
    > > >O(1) scheduler. I decided to document what I found in a web page
    > > >at:
    > > >
    > > > http://www.hpl.hp.com/research/linux/kernel/o1.php
    > >
    > > The page mentions persistent starvation. My own explorations of this
    > > issue indicate that the primary source is always selecting the highest
    > > priority queue.
    >
    >It's deeper than that. The O(1) scheduler doesn't consider
    >actual CPU usage as a factor of CPU priority.

    Oh, there's no doubt in my mind that it's _much_ deeper than my little
    surface scratchings ;-)

    It does consider cpu usage though. Your run history is right there in your
    accumulated sleep_avg. Unfortunately (in some ways, fortunate in others..
    conflict) that information can be diluted down to nothing instantly by new
    input from one wakeup.

    -Mike

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