Am Donnerstag 07 Dezember 2006 16:36 schrieb John Goerzen: > I believe that we should enable CPU frequency scaling, and the ondemand > governer, by default in etch.
Did you read the kernel help for it?: "The support for this governor depends on CPU capability to do fast frequency switching (i.e, very low latency frequency transitions)." The most important word is "very". > * Is compatible with almost all modern hardware, and just won't > load on machines that don't support it > > * Requires only a 10K ondemand module and a 5-15K driver module to be > loaded into the kernel > > Why should it be the default? It shouldn't. > Earlier this morning, I wrote up the procedure [1] to enable CPU > frequency scaling and the ondemand governor. It's about 3 pages, and > not even newbie friendly at that. So the first reason is that people > that don't know about this feature aren't prone to find it, and even if > they find it, they aren't prone to know how to enable it. apt-get install cpufrequtils cpufreq-set -g ondemand Really hard ;) > Secondly, the ondemand governor is very non-invasive. It requires no > userspace daemon. It makes a negligible impact on performance. And if > people do wish to run a userspace daemon, this default will not > interfere with it. I've tried it all over the place. It is stable and > reliable. I already had a system go off with it. Ok, it didn't have low latency switching. > Thirdly, it is ethically the right thing to do. Think about all the > thousands (millons?) of machines that are running Debian. If we save > even an average of 10W per machine, we could be talking about huge > energy savings worldwide. We save our users money on their power and > cooling bills. We reduce air pollution, which has been shown to have > negative health effects. And we reduce greenhouse gas emissions. > > I can't see any reason NOT to do it. > > How would we turn it on by default? You REALLY should take a look at laptop-mode-tools. They can do this for you including loading the proper modules when needed and LOTS of other energy saving technics. And you should take a look at the "conservative" governor, too. And BTW, did you measure the power savings? My WLAN card and monitor backlight eat _all_ the savings and the kernel usually knows how to put the processor to a sleep state. HS -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
