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    SubjectRe: [PATCH v4 0/9] perf, x86: large PEBS interrupt threshold
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    Peter Zijlstra <peterz@infradead.org> writes:
    >
    > No feedback on the correctness aspects of the overflow crap?

    I assume you mean collisions? See below.

    > A quick look at patch 6 reads like you still don't understand the issue
    > right. There are no 'collisions' as such in PEBS record generation, or
    > are there? See the earlier open discussion.

    There can be collisions, but they are in practice extremely rare.

    The only way you can get a lot of collision is if you count
    the same thing multiple times which is not a useful configuration.
    A single monitoring tool only needs a single event once.
    While multiple processes may be configuring multiple events
    at the same time, they will not start them at the same
    time which also prevents collisions.

    -Andi

    --
    ak@linux.intel.com -- Speaking for myself only


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