From: Pavel M. <pa...@uc...> - 2004-01-15 12:19:24
|
Hi! > > > > [Len, could you test and verify this patch, and push it to Linus, please?] > > > > > > > > The current algorithm used by Linux ACPI for passive thermal management has > > > > two shortcomings: > > > > > > ... > > > > > > > +/* If a passive cooling situation is detected, primarily CPUfreq is used, as it > > > > + * offers (in most cases) voltage scaling in addition to frequency scaling, and > > > > + * thus a cubic (instead of linear) reduction of energy. Also, we allow for > > > > + * _any_ cpufreq driver and not only the acpi-cpufreq driver. > > > > + */ > > > > > > Just a stupid question: > > > > > > What is best if processor heat issues (apart turning on the fan)? > > > > > > Reducing voltage of the processor, but still allowing it to run execution > > > at 100% (which is the case if the processor is heating), or reduce > > > amount of time allowed for the processor to execute? > > > > voltage scaling. It offers a much better (quadratic) saving than clock > > modulation (linear saving). Doing both [and you need to do it, as the CPU > > won't run with fewer volts at the same frequency] gives you cubic savings. > > Yes I know. But does it offer more 'cooling'? Of course. If you eat less power, you create less heat. CPU is basically fancy "turn-electricity-into-heat" device. [Have you seen that "first use of PentiumPro in house appliances" picture?] Pavel -- When do you have a heart between your knees? [Johanka's followup: and *two* hearts?] |