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    SubjectRe: O(1) scheduler starvation
    Mike Galbraith wrote:
    > At 09:53 AM 6/18/2003 +0200, Felipe Alfaro Solana wrote:
    >
    >> Hi!
    >>
    >> I've been poking around and found the following link on O(1) scheduler
    >> starvation problems:
    >>
    >> http://www.hpl.hp.com/research/linux/kernel/o1-starve.php
    >>
    >> The web page contains a small test program which supposedly is able to
    >> make two processes starvate. However, I've been unable to reproduce what
    >> is described in the above link. In fact, the CPU usage ratio ranges
    >> between 60-40% or 70-30% in the worst cases.
    >
    >
    > (you're talking about with my monotinic_clock() diff in your kernel right?)
    >
    > If you examine the priorities vs cpu usage, therein lies a big fat bug.
    >
    > I think the fundamental problem is that you can only execute in series,
    > but can sleep in parallel, which makes for more sleep time existing than
    > all execution time combined.

    Would dividing the sleep time by the number of sleepers fix this?
    Or is division a too heavy operation here?

    Helge Hafting

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