Messages in this thread |  | | Date | Tue, 17 Sep 2002 14:18:06 -0700 (PDT) | Subject | Re: do_gettimeofday vs. rdtsc in the scheduler | From | "David S. Miller" <> |
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From: Alan Cox <alan@lxorguk.ukuu.org.uk> Date: 17 Sep 2002 22:28:12 +0100
A bus clock - but things like the x440 have more than one bus clock. Its NUMA. Also the bus clock and rdtsc clock are different - rdtsc is dependant on the multiplier. Shove a celeron 300 and a celeron 450 in a BP6 board with tsc on and enjoy
That's mostly my point.
If the bus clocks differ, then great create some system wide crystal oscillator. That's a detail, the important bit is that you don't need to go out to the system bus to read the tick value, it must be cpu local to be effective and without serious performance impact. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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