CPU frequency scaling problem - laptop users, please check this

A. Kromic akromic at gmail.com
Mon May 30 07:32:55 UTC 2011


On 05/30/2011 04:45 AM, NoOp wrote:
> On 05/29/2011 03:36 PM, A. Kromic wrote:
>> Someone found a workaround for this problem. See
>> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/706089
>>
>> The solution is to add processor.ignore_ppc=1  kernel parameter on boot.
> How interesting... particularly since I'd provided you with:
>
>> Same with Natty. Your initial posts indicated that you had battery/power
>> issues.
>> <http://comments.gmane.org/gmane.linux.ubuntu.user/233787>
>> Is that still the case? Maybe these will help?
>> <http://www.thinkwiki.org/wiki/How_to_make_use_of_Dynamic_Frequency_Scaling>
>> <http://www.thinkwiki.org/wiki/Problem_with_CPU_frequency_scaling>
> in this thread. So let's look at that last uri:
> http://www.thinkwiki.org/wiki/Problem_with_CPU_frequency_scaling
> <quote>
> Solution
>
> Make sure no BIOS setting is limiting the CPU frequency range (like
> "thermal management" = "BALANCED").
>
>     Buy a 90W AC adapter
>     Don't use the laptop without the battery pack
>
> Other solution than using the laptop with the battery pack always
> inserted is to add "processor.ignore_ppc=1" to kernel boot command line.
> This allows to disable BIOS frequency limit, but can be mischievous to
> the computer if it's power consumption is higher than 65W.
> </quote>
>
> and it appears that it still goes back to your power..
>
>
>
Yes, you were right on.

What confused me is the fact that kernels up to the 2.6.32-24 didn't
obey that "protection rule", so I wasn't sure what was causing it. Also,
the machine has worked fine all the time at full speed with the old
kernel, 65W PSU and no battery - I've noticed no problems in use. I'm
also testing it now with latest kernels and the kernel parameter to
disable the check, and so far everything works fine this way too.

I think I have a 90W Lenovo PSU with defective cable somewhere; if I
manage to repair it, according to these instructions everything should
work fine with it...

Thanks.

-- 
A.Kromic
-
No trees were harmed in the sending of this message;
however, a large number of electrons were terribly inconvenienced.


-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/pkcs7-signature
Size: 3642 bytes
Desc: S/MIME Cryptographic Signature
URL: <https://lists.ubuntu.com/archives/ubuntu-users/attachments/20110530/cda0b7d4/attachment.bin>


More information about the ubuntu-users mailing list