Re: [patch] voluntary-preempt-2.6.9-rc1-bk4-Q5

From: Ingo Molnar (mingo_at_elte.hu)
Date: 08/31/04

  • Next message: Norberto Bensa: "Re: 2.6.9-rc1-mm2 nvidia breakage" 
    Date:	Tue, 31 Aug 2004 21:30:29 +0200
To: Thomas Charbonnel <thomas@undata.org>

    * Thomas Charbonnel <thomas@undata.org> wrote:

    > As you can see ~1ms was probably an accident, and the latency does not
    > always come from do_timer. The constant is do_IRQ interrupting the
    > idle thread.

    (do you have any sort of powersaving mode (ACPI/APM) enabled? If yes,
    could you try to tune it down as much as possible - disable any
    powersaving option in the BIOS and in the .config - kill apmd, etc.)

    but i dont think it's powersaving - why would such an overhead show up
    in those functions. The only common thing seems to be that both
    mark_offset_tsc() and mask_and_ack_8259A() does port IO, which is slow -
    but still it shouldnt take ~0.5 msecs!

            Ingo
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  • Next message: Norberto Bensa: "Re: 2.6.9-rc1-mm2 nvidia breakage"