# CPU Throttling

## frobie

I installed a new kernel and now I cannot throttle my CPU I have a centrino mobile chip.  I have the same throttling options in 2.6.12 r10 as I did in 2.6.12 r6 and it worked before I went to r10 and it still works when I use r6 but wont work in r10.  To govern the speeds I am using cpufreqd.  Gnome says the speed is throttling down.  When I go to a terminal and type 

# cat /proc/cpuinfo  under cpu Mhz it says 1597.308 gnome says it should be 800

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## lghman

What does cpufreq-info show you?  It should not only tell you the throttling speed but also what governers and such it is using.

Here is mine just as an example:

```
$ cpufreq-info 

cpufrequtils 0.3: cpufreq-info (C) Dominik Brodowski 2004

Report errors and bugs to linux@brodo.de, please.

analyzing CPU 0:

  driver: centrino

  CPUs which need to switch frequency at the same time: 0

  hardware limits: 600 MHz - 1.60 GHz

  available frequency steps: 1.60 GHz, 1.40 GHz, 1.20 GHz, 1000 MHz, 800 MHz, 600 MHz

  available cpufreq governors: ondemand, userspace, performance

  current policy: frequency should be within 1.40 GHz and 1.60 GHz.

                  The governor "performance" may decide which speed to use

                  within this range.

  current CPU frequency is 1.60 GHz.

```

--sonik

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## frobie

Mine looks the same except for a few speed differences and for the governor it says it is userspace.  When I unplug my laptop current speed goes to 800 mhz but when I type cat /proc/cpuinfo it still says it is going full speed.

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## lghman

What happens if you try to manually set the speed?

```
#cpufreq-set -f 800MHz
```

Also if that doesnt work did you compile the drivers into the kernel or are you loading them as modules?  Because it sounds like you have almost the same setup as me and it works here on r10.

--sonik

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## frobie

That did not work for me either.  I am not sure what is going on, it is very strange?

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## frobie

Any ideas of what I should try next, what are the proper settings I need in the kernel I would be willing to bet that it is where my problem is.

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## lghman

Are you loading the drivers as modules or are they built into the kernel?  If its the former, what does your lsmod show?

```
cpufreq_ondemand        5404  1 

cpufreq_userspace       4188  0 

speedstep_centrino      6484  1 

```

That is what I am using, and I am pretty sure that you have at least a simular setup.

--sonik

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## frobie

Thoes do not show up in lsmod

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## lghman

 *frobie wrote:*   

> Thoes do not show up in lsmod

 

Can you modprobe them in?

--sonik

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## frobie

I can't modprobe any of thoes.  I am not sure what the issue is.

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## frobie

What do you have for the setup in your kernel config?

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## lghman

 *frobie wrote:*   

> What do you have for the setup in your kernel config?

  

```
$ cat .config | grep "CPU"

CONFIG_X86_CPUID=m

# CPU Frequency scaling

CONFIG_CPU_FREQ=y

CONFIG_CPU_FREQ_TABLE=y

CONFIG_CPU_FREQ_DEBUG=y

CONFIG_CPU_FREQ_STAT=y

# CONFIG_CPU_FREQ_STAT_DETAILS is not set

CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y

# CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE is not set

CONFIG_CPU_FREQ_GOV_PERFORMANCE=y

CONFIG_CPU_FREQ_GOV_POWERSAVE=m

CONFIG_CPU_FREQ_GOV_USERSPACE=m

CONFIG_CPU_FREQ_GOV_ONDEMAND=m

# CONFIG_CPU_FREQ_GOV_CONSERVATIVE is not set

# CPUFreq processor drivers

CONFIG_X86_ACPI_CPUFREQ=m

```

Thats what I have set in my kernel config.  Its underneath CPU Frequency Scaling. 

--sonik

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