cpufreq/ does not exist

cpufreq/ does not exist

[Marco Aurelio Stelmar Netto]

Hello,

I have a machine (desktop machine) HP EP-C c10 with a Pentium III
(Coppermine) 1GHz and I'm making some performance tests so I would like
to have the machine processor working at 500 MHz. I have configured the
cpufreq option (kernel 2.6.6) but the cpufreq directory in
/sys/devices/system/cpu/cpu0 does not exist.

I have used the deprecated interface (/proc/cpufreq), but I think it didn't
work (I think  it should show some values here):

cat /proc/cpufreq
     minimum CPU frequency  -  maximum CPU frequency  -  policy

I don't know if I have made some mistake or my cpu does not support the
cpufreq. I have tried to modify the clock frequency via BIOS, but such an
option is not available. All I want is to modify the clock frequency. It
does not need be on-the-fly.

Can anyone give me some help?

Thanks,
Marco

Re: cpufreq/ does not exist

[Dominik Brodowski]

On Thu, Sep 09, 2004 at 11:46:35AM -0300, Marco Aurelio Stelmar Netto wrote:
> 
> Hello,
> 
> I have a machine (desktop machine) HP EP-C c10 with a Pentium III
> (Coppermine) 1GHz and I'm making some performance tests so I would like
> to have the machine processor working at 500 MHz. I have configured the
> cpufreq option (kernel 2.6.6) but the cpufreq directory in
> /sys/devices/system/cpu/cpu0 does not exist.
... 
> I don't know if I have made some mistake or my cpu does not support the
> cpufreq. I have tried to modify the clock frequency via BIOS, but such an
> option is not available. All I want is to modify the clock frequency. It
> does not need be on-the-fly.

A desktop Coppermine Pentium III does not support SpeedStep, so no cpufreq
support exists. Possibly you can change the CPU speed in your system BIOS.

	Dominik

last alternative : program to consume CPU?!

[Marco Aurelio Stelmar Netto]

The BIOS of my machine does not support the modification of the CPU speed.

My problem is that I have a homogeneous cluster composed of 16 machines
and I need to perform some tests of my application on a heterogeneous
cluster. So my first option was to change the cpu speed in the BIOS, but
failed. The second option was to find some support in the linux itself.
I have found the cpufreq, but failed. My last option is to implement or
find a program to consume a percentage of CPU. Do you know where I can
find a good program to perform this task? Or do you know another alternative
to solve my problem?

Thank you very much for your attention.

Marco

On Thu, 9 Sep 2004, Dominik Brodowski wrote:

> On Thu, Sep 09, 2004 at 11:46:35AM -0300, Marco Aurelio Stelmar Netto wrote:
> >
> > Hello,
> >
> > I have a machine (desktop machine) HP EP-C c10 with a Pentium III
> > (Coppermine) 1GHz and I'm making some performance tests so I would like
> > to have the machine processor working at 500 MHz. I have configured the
> > cpufreq option (kernel 2.6.6) but the cpufreq directory in
> > /sys/devices/system/cpu/cpu0 does not exist.
> ...
> > I don't know if I have made some mistake or my cpu does not support the
> > cpufreq. I have tried to modify the clock frequency via BIOS, but such an
> > option is not available. All I want is to modify the clock frequency. It
> > does not need be on-the-fly.
>
> A desktop Coppermine Pentium III does not support SpeedStep, so no cpufreq
> support exists. Possibly you can change the CPU speed in your system BIOS.
>
> 	Dominik
>

Re: last alternative : program to consume CPU?!

[GoatZilla]

Uhm...

Treat the machine as a dual CPU resource, and load it down with 2 jobs
instead of 1?




On Thu, 9 Sep 2004 13:35:56 -0300 (BRT), Marco Aurelio Stelmar Netto
<stelmar@cpad.pucrs.br> wrote:
> 
> The BIOS of my machine does not support the modification of the CPU speed.
> 
> My problem is that I have a homogeneous cluster composed of 16 machines
> and I need to perform some tests of my application on a heterogeneous
> cluster. So my first option was to change the cpu speed in the BIOS, but
> failed. The second option was to find some support in the linux itself.
> I have found the cpufreq, but failed. My last option is to implement or
> find a program to consume a percentage of CPU. Do you know where I can
> find a good program to perform this task? Or do you know another alternative
> to solve my problem?
> 
> Thank you very much for your attention.
> 
> Marco
> 
> On Thu, 9 Sep 2004, Dominik Brodowski wrote:
> 
> > On Thu, Sep 09, 2004 at 11:46:35AM -0300, Marco Aurelio Stelmar Netto wrote:
> > >
> > > Hello,
> > >
> > > I have a machine (desktop machine) HP EP-C c10 with a Pentium III
> > > (Coppermine) 1GHz and I'm making some performance tests so I would like
> > > to have the machine processor working at 500 MHz. I have configured the
> > > cpufreq option (kernel 2.6.6) but the cpufreq directory in
> > > /sys/devices/system/cpu/cpu0 does not exist.
> > ...
> > > I don't know if I have made some mistake or my cpu does not support the
> > > cpufreq. I have tried to modify the clock frequency via BIOS, but such an
> > > option is not available. All I want is to modify the clock frequency. It
> > > does not need be on-the-fly.
> >
> > A desktop Coppermine Pentium III does not support SpeedStep, so no cpufreq
> > support exists. Possibly you can change the CPU speed in your system BIOS.
> >
> >       Dominik
> >
> 
> _______________________________________________
> Cpufreq mailing list
> Cpufreq@www.linux.org.uk
> http://www.linux.org.uk/mailman/listinfo/cpufreq
>

Re: last alternative : program to consume CPU?!

[Marco Aurelio Stelmar Netto]

Hi,
I'm almost there.
A friend of mine gave me a program to consume CPU. I'm just performing
some tuning in it. Of course it is not an elegant solution, but I think
it will resolve my problem. Note that suggestions are still very welcome
;)

--------------------------------
#define RESOLUTION 1000000

struct itimerval value;
unsigned long busy, idle;

void sigHandler(int signum) {
  usleep(idle);
  setitimer(ITIMER_REAL, &value, NULL);
}

int main(int argc, char **argv) {

  struct sigaction sa;
  float perc;

  if(argc != 2) {
    printf("Usage: %s <value>\n", argv[0]);
    exit(0);
  }

  perc = atof(argv[1]);

  if((perc < 0) || (perc > 1)) {
    printf("Value must be between 0 and 1\n");
    exit(0);
  }

  busy = perc*RESOLUTION;
  idle = (1-perc)*RESOLUTION;

  memset(&sa, 0, sizeof(sa));
  sa.sa_handler = sigHandler;

  sigaction(SIGALRM, &sa, NULL);

  memset(&value, 0, sizeof(struct itimerval));
  value.it_value.tv_usec = busy;

  setitimer(ITIMER_REAL, &value, NULL);

  for(;;);
  return 0;
}
-------------------------------

Thanks for your suggestion.

On Thu, 9 Sep 2004, GoatZilla wrote:

> Uhm...
>
> Treat the machine as a dual CPU resource, and load it down with 2 jobs
> instead of 1?
>
>
>
>
> On Thu, 9 Sep 2004 13:35:56 -0300 (BRT), Marco Aurelio Stelmar Netto
> <stelmar@cpad.pucrs.br> wrote:
> >
> > The BIOS of my machine does not support the modification of the CPU speed.
> >
> > My problem is that I have a homogeneous cluster composed of 16 machines
> > and I need to perform some tests of my application on a heterogeneous
> > cluster. So my first option was to change the cpu speed in the BIOS, but
> > failed. The second option was to find some support in the linux itself.
> > I have found the cpufreq, but failed. My last option is to implement or
> > find a program to consume a percentage of CPU. Do you know where I can
> > find a good program to perform this task? Or do you know another alternative
> > to solve my problem?
> >
> > Thank you very much for your attention.
> >
> > Marco
> >
> > On Thu, 9 Sep 2004, Dominik Brodowski wrote:
> >
> > > On Thu, Sep 09, 2004 at 11:46:35AM -0300, Marco Aurelio Stelmar Netto wrote:
> > > >
> > > > Hello,
> > > >
> > > > I have a machine (desktop machine) HP EP-C c10 with a Pentium III
> > > > (Coppermine) 1GHz and I'm making some performance tests so I would like
> > > > to have the machine processor working at 500 MHz. I have configured the
> > > > cpufreq option (kernel 2.6.6) but the cpufreq directory in
> > > > /sys/devices/system/cpu/cpu0 does not exist.
> > > ...
> > > > I don't know if I have made some mistake or my cpu does not support the
> > > > cpufreq. I have tried to modify the clock frequency via BIOS, but such an
> > > > option is not available. All I want is to modify the clock frequency. It
> > > > does not need be on-the-fly.
> > >
> > > A desktop Coppermine Pentium III does not support SpeedStep, so no cpufreq
> > > support exists. Possibly you can change the CPU speed in your system BIOS.
> > >
> > >       Dominik
> > >
> >
> > _______________________________________________
> > Cpufreq mailing list
> > Cpufreq@www.linux.org.uk
> > http://www.linux.org.uk/mailman/listinfo/cpufreq
> >
>
> _______________________________________________
> Cpufreq mailing list
> Cpufreq@www.linux.org.uk
> http://www.linux.org.uk/mailman/listinfo/cpufreq
>