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Date: Sun, 30 Sep 2012 13:44:14 +0200 From: Uwaysi Bin Kareem <uwaysi.bin.kareem@...adoxuncreated.com> To: linux-kernel@...r.kernel.org Subject: The 10ms averager in fair.c Hiya. I just had an initial look at fair.c There seems to be a 10ms averager in there? You are aware that that means you work on delayed values? Isn`t that counterintuitive to the principle of sharing? That means short bursts of cpu-use will be filtered out, and given less cpu time. Starting applications won`t have their cpu-usage before 5ms, which is quite a bit on modern machines. Well if you use a linearphase filter, I don`t know what kind of averager you use. The best would ofcourse be to use a minimalphase gaussian averager. Which might be overkill. Atleast a one-pole iir, buf = buf + (-buf + in) * cut)); One pole IIRs also have a better frequency response. When you are working with low-latencies, wouldn`t it be better if such things are tuned for target latency. I think few care about latency after 0.2ms. So say the filter should be set to 0.4ms max. Why would you want to filter cpu-usage also really? Peace Be With You. (please CC me.) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.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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