On Fri, 23 Apr 2010 10:38:28 +0200 Pavel Machek <pavel@xxxxxx> wrote: > On Fri 2010-04-23 06:52:48, Arjan van de Ven wrote: > > On Fri, 23 Apr 2010 07:24:39 +0200 > > Pavel Machek <pavel@xxxxxx> wrote: > > > > > > > > Well, and now, if you do something like cat /dev/<your usb1.1 > > > hdd> > /dev/null, you'll keep cpu on max frequency. Not a problem > > > hdd> > for new > > > core i7, but probably big deal for athlon 64. > > > > do you have facts not speculation for this? Does the athlon 64 > > really > > You want the patch applied, you should be able to justify it. You make a claim... all I am asking if you are doing just random guess or basing this on facts. The machines I have access to don't show any impact during actual idle, because they stop clocks and generally even lower the voltage. You make a claim that a certain machine does not do either... all I'm asking if that claim is based on data or on speculation. > > > keep its voltage high during idle? That would surprise me greatly... > > (and if it does, does it matter? the clock is stopped anyway there) > > Yes, I believe it keeps voltage up, and as a leakage is big part of > power consumption there, stopped clocks will not help much. again do you have actual data? > I believe you are developing on wrong machine. Seems like core i7 just > wants max frequency, all the time. Older designs were not like that. > > Do you have early intel speedstep machine near you? oh I use many different machines. the intel machines at least stop the clocks, and for a really long time also lower the frequency in idle. (especially during deeper C states, but even during C1) > > > the only place where my patch makes a real difference is when the > > cpu is idle due to blocking IO! So do you have data that the athlon > > 64 gets too hot if you select a high frequency during an idle > > period, where the clock is already stopped? > > iirc even idle power consumption was much higher when on max > voltage... I'll get some numbers from my old notes; I no longer have > the hw. make sure it's data based on tickless... without tickless we were never really idle ;-( -- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
