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    SubjectRe: [PATCH] Load balancing problem in 2.6.2-mm1
    >     Good stuff, I just gave the patch a spin and things seem a little
    > calmer. However Im still seeing a lot of balancing going on within a
    > node.
    >
    > This is a clearly recognizable edge case, so I'll try drawing this up on
    > some paper and see if I can suggest another patch. There's no good reason
    > to move one lone process from a particular processor to another idle one.
    >
    > But it also approaches a question that's come up before: if you have 2
    > tasks on processor A and 1 on processor B, do you move one from A to B?
    > One argument is that the two tasks on A will take twice as long as
    > the one on B if you do nothing. But another says that bouncing a task
    > around can't correct the overall imbalance and so is wasteful. I know
    > of benchmarks where both behaviors are considered important. Thoughts?

    It's the classic fairness vs throughput thing we've argued about before.
    Most workloads don't have that static a number of processes, but it
    probably does need to do it if the imbalance is persistent ... but much
    more reluctantly than normal balancing. See the patch I sent out a bit
    earlier to test it - that may be *too* extreme in the other direction,
    but it should confirm what's going on, at least.

    M.

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