cpuspeed issue, present in Fedora Core 6 and in Fedora 7

[Dean S. Messing]

Christian Burger writes:
> > 
> > On Tue, 2007-06-05 at 11:29 -0500, Christian Burger wrote:
> > > I also get a lot of ACPI "can't turn cooling device 'on'" messages
> > > in dmesg.
> > 
> > I see something similar scroll by when I hibernate one of my desktop
> > PCs.  Does your motherboard have several FAN connectors, with some of
> > them unused?  Perhaps it's complaining about *one* of them not
> > indicating that a fan is spinning, when it doesn't really matter.
> > 
> 
> I would have to double check when I am at home, but I'm pretty sure it
> doesn't.  This is a SFF pc where every bit of available space is utilized,
> so I don't believe there are any unused connectors.  The messages in dmesg
> don't bother me as much as my cpu running at it's slowest speed.  Are there
> any kernel arguments I could pass to disable the monitoring? 

I'm not sure about the "cooling" messages you mentioned in the
original post, but you can try the following.

(I'm not responsible if you burn up your CPU due to a broken fan :-)

1) Become root and `cd /sys/devices/system/cpu/cpu0/cpufreq'

If it exists then:

2) # cat scaling_available_frequencies 

   On my laptop, I get "1867000 1600000 1333000 1067000 800000"
   These are the possible cpu speeds my cpu can be set to.

3) # cat scaling_available_governors

   On my laptop I get "ondemand userspace performance"

4) # cat cpuinfo_cur_freq
   # cat scaling_governor

   These contain (surpise) the current cpu frequency and current
   "scaling governer".  Your cpu freq should be in the list you get
   from 2) and the current governor from the list you get from 3).

Finally

5) # cat /sys/module/processor/parameters/max_cstate

   That's the maximum "power saving" state your processor can be put into.

Record the values from 4) and 5) and then do:

# echo 1           > /sys/module/processor/parameters/max_cstate
# echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

Now have a look at your "cpuinfo_cur_freq".  Hopefully the number
will have changed from one of the lower numbers in the list to the
highest.

If you want to change things back than simply modify the
"echo" lines above to have the origianl values.

Let us know what you find.

Dean