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    Subjecttimer interrupt stucks using tickless kernel
    Hi all,

    I have configured my kernel ( so that I get periodic ticks from
    the timer interrupt (i.e. tickless is not configured) with a rate determined
    by the HZ value. I've also checked the "high resolution timer support"
    and also SMP support. The posblem is that the timer is getting incremented
    very slowly (way slower than the HZ value), just like it would be if the
    kernel was tickless. Is there an explanation for that? How can I get
    timer ticks?

    AFAI understand, the HPET timer is used through the IO-APIC controller to
    trigger the processors (N.B. if the "High Resolution Timer Support" option
    wasn't checked, the timer used would be PIT, right?) and each processor's
    LAPIC timer is used for time keeping. Please correct me if I am wrong.

    Another question is how the LAPIC timner's rate is determined? In my case,
    it seams that an interurpt by LAPIC timer is generated very appoximately
    0.25 sec (that is HZ which is 1000 * 4) but I can't understand why.

    Thanks in advance.

     \ /
      Last update: 2009-12-07 16:27    [W:0.025 / U:8.000 seconds]
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