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    SubjectRe: [Lse-tech] [patch] sched-domain cleanups, sched-2.6.5-rc2-mm2-A3
    >> It doesn't do load balance in wake_up_forked_process() and is
    >> relatively non aggressive in balancing later. This leads to the
    >> multithreaded OpenMP STREAM running its childs first on the same node
    >> as the original process and allocating memory there. [...]
    >
    > i believe the fix we want is to pre-balance the context at fork() time.
    > I've implemented this (which is basically just a reuse of
    > sched_balance_exec() in fork.c, and the related namespace cleanups),
    > could you give it a go:
    >
    > http://redhat.com/~mingo/scheduler-patches/sched-2.6.5-rc2-mm2-A5
    >
    > another solution would be to add SD_BALANCE_FORK.
    >
    > also, the best place to do fork() blancing is not at
    > wake_up_forked_process() time, but prior doing the MM copy. This patch
    > does it there. At wakeup time we've already copied all the pagetables
    > and created tons of dirty cachelines.

    How are you going to decide whether to rebalance at fork time or exec time?
    Exec time balancing is a *lot* more efficient, it just doesn't work for
    things that don't exec ... cloned threads would certainly be one case.

    M.

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