CPU frequency scaling problem - laptop users, please check this

[Joep L. Blom]

On 24/05/11 13:00, A. Kromic wrote:
> I have a problem of CPU frequency scaling not working with kernels newer
> than 2.6.32-24 (which I already discussed here a while ago). The bug is
> reported here: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/706089
>
> The problem is, this problem seems to be ignored (nobody reacted at all
> to fix this, something that perhaps deserves further comments); one of
> the reasons could be that most people _have_no_idea_ what frequency
> their CPU is running at! Therefore, probably there aren't enough reports
> for anyone to investigate this...
>
> So I'm asking people with Core2/Centrino Duo laptops if they could check
> the frequency their CPU is running at. At the bug tracker, there is one
> reply from an AMD Turion64 user to have the same problem, so perhaps
> users of such machines could give it a try...
>
> How to check it? One way is from the console, simply do:cat
> /proc/cpuinfo. Within the results should be something like this:
>
> model name    : Intel(R) Pentium(R) Dual  CPU  T2330  @ 1.60GHz
> stepping    : 13
> cpu MHz        : 800.000
>
> The model name says my CPU normally works at 1.60 GHz, and below the
> actual frequency is shown. For me, it normally should say "1600.000",
> which it does with older kernels, but this happens with the newer ones.
>
> The other way (perhaps easier) for Gnome users is to add the CPU
> Frequency Scaling Monitor applet to a panel and see what frequency it
> shows, the expected one or lower.
>
> A notice, though... The default CPU governor lowers CPU frequency when
> the CPU is unloaded. So, if you get a low frequency, most likely is that
> everything works correct, you should change the frequency or governor
> and recheck. Also, if you get a frequency which is not the lowest one
> (but you should know what frequency is the lowest for your CPU), the
> scaling should be ok.
>
> On to changing the frequency. With Gnome applet it is simple, just click
> on it and a menu will be shown where you can change the governor (you
> should select "performance") or frequency (you should select any
> frequency but the lowest, or simpy the highest one). If your CPU now
> doesn't work at the lowest frequency from the menu, or works at the
> exact one you chose, everything is fine.
>
> In ccommandline you can try:
>
> sudo cpufreq-set -g performance
>
> (You should have /cpufrequtils/ package installed.) You can also set a
> frequency:
>
> sudo cpufreq-set -f 1600
>
> (This is for my CPU, you should set yours to a supported frequency.)
>
>
> However, if you find your CPU doesn't work at the expected frequency,
> please see the above bugreport link and check "Affects Me" there. Thanks!
>
> You may also be surprised at what you find by those tests ;)
>
> --
> A.Kromic
> -
> No trees were harmed in the sending of this message;
> however, a large number of electrons were terribly inconvenienced.
>

William,
I have, for several years an AMD Phenom II (4-core) and my cores, 
switch, depending on the load, between 800 MHz and 2600 MHz. However, 
I'm running Lucid 10.04 with kernel 2.6.32-26-generic.
I read so many stories about problems with the younger non LTS versions 
that I don't want to "upgrade". Why do people always think that 
newer=better? The LTS versions upgrade - as far as I know - the various 
applications - and the kernel - for optimisation and I use my system to 
perform some work not to play with new technical "toys". But that's only 
my 0,02 €.
Joep