Messages in this thread | | | Date | Mon, 13 Dec 2004 20:04:14 +0100 | From | Pavel Machek <> | Subject | Re: dynamic-hz |
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Hi!
> > > Lets take an example. Lets say that: > > > * a CPU runs at about 245mA when active > > > * 90mA when inactive > > > * the timer interrupt takes 2us to execute 1000 times a second > > > * no other processing is occuring > > > > Now take a real laptop and the numbers are in the 20W (15A) range. > > Roughly 650mA for my laptop while idle or just under 7W - by calculation > from battery capacity and measured lifetime. The question is how much > of that is due to the CPU itself and how much is due to the > peripherals.
On Arima notebook here, whole machine takes 28W on 800MHz, idle (measured using external power meter), 33W with max backlight, and 68W at 2GHz, computing. Going to HZ=100 makes it one Watt less. I'd say that's quite significant. [17W number was based on internal power meter when running on battery].
So yes, CPU *is* taking more than all other perihepals. Pavel -- People were complaining that M$ turns users into beta-testers... ...jr ghea gurz vagb qrirybcref, naq gurl frrz gb yvxr vg gung jnl! - 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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