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    SubjectSystem clock frequency offset changes drastically across reboots
    Hello everyone,

    I'm using 2.6.20.7-rt8 on a P3.

    I've noticed that the frequency offset of my system clock (computed
    either by ntpd, or by hand) changes drastically across reboots.

    By drastically, I mean +/- 60 ppm every time I reboot.

    Apparently this is caused by some imprecision in the frequency
    estimation done in calculate_cpu_khz() (arch/i386/kernel/tsc.c)

    My brutally crude work-around was to skip the computation altogether and
    hard-code the "correct" value for cpu_khz.

    http://linux.kernel.free.fr/cpu_khz.adlink

    Has this issue been investigated more thoroughly by other users?

    Regards.
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