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    SubjectRe: [patch 0/4] perf_counter tools: support annotation of live kernel modules
    On Thu, 2009-07-02 at 09:42 +0200, Ingo Molnar wrote:

    (squirrels suggestions away for later reference)

    > Btw, another thing: we are thinking about making -F 1000 (1 KHz
    > auto-freq sampling) the default for perf top and perf record. This
    > way we'd always gather enough data (and never too much or too little
    > data), regardless of the intensity of the workload. Have you played
    > with -F before, what's your general experience about it? It's
    > particularly useful for 'rare' and highly fluctuating events like
    > cache-misses.
    > Maybe 1KHz is a bit too low - Oprofile defaults to 100000 cycles
    > interval by default which is about 10 KHz on a 1GHz box and 30 KHz
    > on a 3GHz box. Perhaps 10 KHz is a better default?

    My default usage is 1000Hz to keep overhead low. Works fine for me.


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