[ltp] CPU running ??? but why????

[Florian Reitmeir]

On Sun, 08 Jun 2008, Arno Trautmann wrote:

> Florian Reitmeir wrote:
>> On Sat, 07 Jun 2008, Peter F. Patel-Schneider wrote:
>>
>>> As far as I know, this is an unexplained phenomenon that has been around
>>> for at least a year now.  My Lenovo T60p exhibits this behaviour
>>> sometimes, but not all the time.  Even more strangely, the aberrant
>>> behaviour comes and goes - for a few days it happens quite reqularly,
>>> then there is no problem for weeks on end.
>>>
>>> Several people, myself included, have asked in various fora about the
>>> problem, including the powertop mailing list, accessible at
>>>   http://www.bughost.org/mailman/listinfo/power
>>> see   http://www.bughost.org/pipermail/power/2007-May/000337.html  
>>> for the first report that I can find.  I just noticed a recent report 
>>> on
>>> the problem
>>>   http://www.bughost.org/pipermail/power/2008-June/001371.html
>>>
>>> So what is causing the problem?  The guessing, and as far as I know it
>>> is only guessing, is that some DMA activity is causing the wakeups, but
>>> I don't even know enough about the situation to figure out whether
>>> explanation makes any sense.  Even if this is the case, I haven't seen
>>> any hints on how to attempt to fix the problem, or even which of the
>>> many devices built in to my T60p is the source.  I don't even know how
>>> widespread the problem is.
>>>
>>> All in all, quite frustrating.
>>
>> just run powetop in one terminal
>> and run an other terminal in which you remove kernel modules, one by one.
>>
>> typical these kernel modules first:
>> 	- usb
>> 	- firewire
>> 	- sound hardware
>> 	- yenta socket
>>
>> take your time, if its a hardware problem you should be able to debug it, in
>> about 30 mins.
>
> That sounds good? but I don?t have any idea how to do this? I?m quite  
> new to linux, so could you give me some concrete commandos or a page  
> where I can find some examples? I would be very happy if I could track  
> it down on this way!
ok

open 2 terminals ... just gome-terminals oder xterms or ..
make sure you have root permissions, so do a 'su -' and enter the root
password.


now you can start powertop in one terminal

to list the loaded modules (=drivers) type 'lsmod'
to unload a module type 'modprobe -r <module name>'
to load a module type 'modprobe <module name>'

Note: some modules depend on others.. so lsmod gives you on the left side a
column of module names, on the right side which other module needs the
current module.

And normally you can't crash your Laptop, because the kernel denies access to
modules which are in use, _but_ do not rely on that.


then.. just unload modules, and look at powertop.


-- 
Florian Reitmeir