Messages in this thread | | | From | "Michael S. Zick" <> | Subject | Re: Linux 2.6.30-rc8 [also: VIA Support] | Date | Sat, 6 Jun 2009 07:17:44 -0500 |
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On Thu June 4 2009, Linus Torvalds wrote: > > On Thu, 4 Jun 2009, Michael S. Zick wrote: > > > > Yes, I build test cases with and without - - > > It was a fixed-speed kernel build that first hit the 4 hour up-time mark. > > I just reposted that build today (the -09143lk). > > > > > Features like that easily put a huge stress on power regulators etc, if > > > they result in sudden changes in current draw. Underspecced capacitors > > > etc can cause CPU "brown-outs", which in turn can easily cause total > > > failure. > > > > There is also a possible thermal issue with these machines - - > > I doubt that VIA runs their qualification testing in bake ovens; > > which is what NetBook cases amount too. ;) > > If the fixed-speed case runs for longer, it's not likely to be a thermal > issue. The fixed speed case should be the higher-power one. >
I can respond to that point now; VIA Tech has answered some of my questions -
The mainstream kernel, e_powersaver, is *under-clocking* my machine -
The cpuid instruction provides the minimum and maximum GSF values (Guaranteed Stable Frequency) for that processor mask run - Passing that on as the lower and upper limits to e_powersaver should stop that problem. Will be testing this RSN.
Once you start operating the processor outside of the reported-by-silicon mask limits - quote: "there is no quarantee of stable operation" - -
To that I add my opinion: For a severely under-clocked machine (already possibly un-stable) - - Thermal effects are almost certain to be present.
To paraphrase VIA Tech once again: "Don't do that." ;)
Mike
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