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    SubjectRe: Stolen and degraded time and schedulers
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    On Wed, 2007-03-14 at 09:37 -0700, Jeremy Fitzhardinge wrote:
    > Daniel Walker wrote:
    > > Then your direction is wrong, sched_clock() should be constant ideally
    > > (1millisecond should really be 1millisecond).
    >
    > Rather than repeating myself, I suggest you read my original post
    > again. But my point is that "I was runnable on a cpu for 1ms of real
    > time" is a meaningless measurement: you want to measure "I ran for 1
    > cpu-ms", which is a unit which depends on how work a particular CPU does
    > in relationship to other CPUs on the system, or even itself at some
    > previous time.

    I understood, I just don't agree that you suggested modification are the
    correct ones to make.

    > > Like I said in the last
    > > email, change the scheduler to make it aware of the variable quantum
    > > values.
    >
    > I suppose you could, but that seems more complex. I think you could
    > encode the same information in the measurement of how much work a cpu
    > actually got done while a process was scheduled on it.

    I know it's more complex, but that seems more like the "right" thing to
    do.

    Daniel

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