Re: Intel Atom N450 & Kernel Config Options re: SMP
On Fri, Jul 30, 2010 at 12:52 AM, Stan Hoeppner <stan@hardwarefreak.com> wrote:
> Arthur Machlas put forth on 7/29/2010 12:01 PM:
>
>> Things are running nicely, but the problem I hoped
>> to resolve hasn't been. Namely, the lowest frequency my cpu can reach
>> is 1Ghz... instead of the 800Mhz that it reaches on windows and in the
>> spec sheets.
>>
>> Advice on how to proceed from here is greatly appreciated.
>
> I led you to the well but it's up to you to drink Arthur. You didn't read the
> help screens. All the frequency info you need is there. It is the key to you
> succeeding at this. You may have to experiment some, but that's a requirement
> when rolling one's own kernels. Welcome to the club. It's rarely "easy". ;)
>
Asking on here isn't my first attempt at figuring things out. My
kernel config work is based on Greg KM's book "The Linux Kernel In A
Nutshell". So, not only have I read the help screens, but I've also
read a pretty decent book by one of the kernel's prime maintainers.
I should have been more clear about the advice I was hoping for, since
there is nothing wrong with my kernel config, I was looking for advice
about how to go about further debugging this issue of not having full
frequency range. I wanted to give fixing it a solid try before filing
a bug against the kernel itself.
> BTW, I'm curious as to your motivations for this. Is this basically a
> "Windows can do 800MHz, so $deity dammit, Linux should be able to do it as
> well!" thing?
Not as such. More like a my processor is supposed to scale from 800Mhz
to 1.6Ghz, and its strange that it doesn't. I wonder why.
> In practical terms Arthur, you will not notice a meaningful
> difference in thermal output or current draw (battery consumption) between
> 800MHz and 1GHz with the n450. The n450 has a TDP of 5.5 watts at 1.66GHz.
> Thus you won't even save 1 watt going from 1GHz to 800MHz in power save mode.
> It'll be something like 300 milliwatts or less. This exercise of yours is
> futile if your goal is a _practical_ difference in system operation.
I suppose that will have to count as advice on how to proceed, but I
hope you'll forgive me if I continue to search for an answer. Your
comments are reassuring to me though, that it isn't a serious problem,
and I do thank you for that.
At this point, I'm thinking it's a problem with the kernel or a
problem with my bios, and I think there are some kernel command line
parameters I can use to test the latter in Greg's book.
Best wishes,
AM
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