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    SubjectRe: [RFC PATCH 2/3 v2] perf: Implement Nehalem uncore pmu
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    On Thu, Nov 25, 2010 at 7:20 PM, Andi Kleen <andi@firstfloor.org> wrote:
    >> Yep, I see no reason to dis-allow sampling. Sure its hard to make sense
    >> of it, but since there are people who offline all but one cpu of a
    >> package,
    >
    > Assuming they don't have any active PCI devices either.
    >
    Good point.

    >> I bet there are people who will run just one task on a package
    >> as well.
    >
    > In that case the sampling has a 1/NUM-CPU-THREADS-IN-PACKAGE chance
    > to report the right task (or actually somewhat less because the measurement
    > skew for uncore is much higher than for normal events)
    >
    > Really for per core measurements using the OFFCORE events is much better.
    >
    yes, OFFCORE_RESPONSE is much more useful.


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