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    SubjectRe: [PATCH 00/27] Latest numa/core release, v16

    * Ingo Molnar <mingo@kernel.org> wrote:

    > This is an entirely valid line of inquiry IMO.

    Btw., what I did was to simply look at David's profile on the
    regressing system and I compared it to the profile I got on a
    pretty similar (but unfortunately not identical and not
    regressing) system. I saw 3 differences:

    - the numa emulation faults
    - the higher TLB miss cost
    - numa/core's failure to handle 4K pages properly

    And addressed those, in the hope of one of them making a
    difference.

    There's a fourth line of inquiry I'm pursuing as well: the node
    assymetry that David and Paul mentioned could have a performance
    effect as well - resulting from non-ideal placement under
    numa/core.

    That is not easy to cure - I have written a patch to take the
    node assymetry into consideration, I'm still testing it with
    David's topology simulated on a testbox:

    numa=fake=4:10,20,20,30,20,10,20,20,20,20,10,20,30,20,20,10

    Will send the patch out later.

    Thanks,

    Ingo


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