John McCabe-Dansted wrote: > After reading > http://www.bughost.org/pipermail/power/2007-May/000166.html > I've filed a bug about Ubuntu's use of ignore_nice_load: > https://bugs.launchpad.net/ubuntu/+source/sysvinit/+bug/192303 > > I understand that due to the "Race to idle", it would actually save > power to run nice tasks at full speed. Thus, except in edge cases, > such as when the nice task caught in a loop, the ignore_nice_load > option is pointless. > > Would you agree that ignore_nice_load should not be set by default?
yes with one exception: there's a class of nice tasks such as [EMAIL PROTECTED] and stuff where people do want it ignored > > Secondly, as setting the CPU frequency saves little power during idle, > why do you recommend ondemand rather than performance? the thing is, the cpu goes to lowest settings during idle. Transitions cost power, so if you go in and out of idle for very brief periods of time (say to service interrupts), you actually are better off staying at low settings. Ondemand ends up doing exactly that. > > Also what up_threshold do you recommend? (Ubuntu uses 31% by default, > but AFAICT, race to idle would mean that a lower up_threshold would > actually save power) 31% is just a silly value that is so wrong on many levels; they should just leave the kernel default. > Finally, are there older CPUs for which the "conservative" governor > would make sense? Not from Intel afaik, maybe from AMD. > _______________________________________________ Power mailing list [email protected] http://www.bughost.org/mailman/listinfo/power
