Check CPU for throttling
 

Hi list!

Does someone know a tool that measures CPU performance and gives
live-updates on it?

My problem is as follows:
I have a desktop PC where the case is too small to include the custom
CPU cooler with fan. However, because the power supply sits directly
above the CPU and the CPU cooler is reasonably effective, I've simply
removed the fan from the CPU cooler and let the fan from the power
supply act as the CPU fan. This works surprisingly well and usually, the
CPU runs at 50°C.

During tests with app-benchmarks/cpuburn, the CPU got as hot as 74°C.
According to lm_sensors, this is the threshold for "critical"
temperature (though I find it a bit low - I've seen CPUs running as high
as 90°C). Therefore I suspect that the CPU gets throttled but I cannot
verify this with cpuburn because this tool does not output performance
figures.

Because of that I'm in a need for a similar tool that also outputs FIPS,
iterations per second or some other figure while running so that I can
monitor it for any performance drops. I guess I could just use mencoder
and watch framerates or I could code something myself but maybe someone
knows a better tool for this.

Thanks in advance!
Florian Philipp

Check CPU for throttling
 

On 05/08/2011 11:21:06 AM, Florian Philipp wrote:

sys-process/atop shows current CPU freqency
I use it to check the effect of sys-power/powernowd

Helmut.

> Hi list!
>
> Does someone know a tool that measures CPU performance and gives
> live-updates on it?
>
> My problem is as follows:
> I have a desktop PC where the case is too small to include the custom
> CPU cooler with fan. However, because the power supply sits directly
> above the CPU and the CPU cooler is reasonably effective, I've simply
> removed the fan from the CPU cooler and let the fan from the power
> supply act as the CPU fan. This works surprisingly well and usually,
> the
> CPU runs at 50°C.
>
> During tests with app-benchmarks/cpuburn, the CPU got as hot as 74°C.
> According to lm_sensors, this is the threshold for "critical"
> temperature (though I find it a bit low - I've seen CPUs running as
> high
> as 90°C). Therefore I suspect that the CPU gets throttled but I
> cannot
> verify this with cpuburn because this tool does not output
> performance
> figures.
>
> Because of that I'm in a need for a similar tool that also outputs
> FIPS,
> iterations per second or some other figure while running so that I
> can
> monitor it for any performance drops. I guess I could just use
> mencoder
> and watch framerates or I could code something myself but maybe
> someone
> knows a better tool for this.
>
> Thanks in advance!
> Florian Philipp
>
>



--
Helmut Jarausch
Lehrstuhl fuer Numerische Mathematik
RWTH - Aachen University
D 52056 Aachen, Germany

Check CPU for throttling
 

Have you considered installing a low profile fan like
Delta EFB0612MA 60x60x10[mm] ?

Check CPU for throttling
 

Am 08.05.2011 13:01, schrieb Thanasis:
> Have you considered installing a low profile fan like
> Delta EFB0612MA 60x60x10[mm] ?
>

I did. But I still had the current cooler available. I don't want to
spend money on a new cooler if it is not necessary. Since I know even
Pentium 4 cooled in that way, it was worth a try.

Check CPU for throttling
 

On Sunday 08 May 2011 12:59:57 Helmut Jarausch wrote:
> On 05/08/2011 11:21:06 AM, Florian Philipp wrote:
>
> sys-process/atop shows current CPU freqency
> I use it to check the effect of sys-power/powernowd

why are you using powernowd?

Check CPU for throttling
 

On 05/10/2011 02:36:33 AM, Volker Armin Hemmann wrote:
> On Sunday 08 May 2011 12:59:57 Helmut Jarausch wrote:
> > On 05/08/2011 11:21:06 AM, Florian Philipp wrote:
> >
> > sys-process/atop shows current CPU freqency
> > I use it to check the effect of sys-power/powernowd
>
> why are you using powernowd?
>
Why not? It's a daemon which reduces the CPU speed under certain
circumstances.
This not only saves power but it reduce the noise produced by the fan.

Helmut.

Check CPU for throttling
 

On Tuesday 10 May 2011 08:27:42 Helmut Jarausch wrote:
> On 05/10/2011 02:36:33 AM, Volker Armin Hemmann wrote:
> > On Sunday 08 May 2011 12:59:57 Helmut Jarausch wrote:
> > > On 05/08/2011 11:21:06 AM, Florian Philipp wrote:
> > >
> > > sys-process/atop shows current CPU freqency
> > > I use it to check the effect of sys-power/powernowd
> >
> > why are you using powernowd?
>
> Why not? It's a daemon which reduces the CPU speed under certain
> circumstances.

just like the kernel. Only the kernel does it better.

> This not only saves power but it reduce the noise produced by the fan.

fanspeed - if you have a pwm fan.

Seriously, powernowd is so not needed. Just built a kernel with ondemand cpu
governor. You are done.

Check CPU for throttling
 

On 05/10/2011 02:44:26 PM, Volker Armin Hemmann wrote:
> On Tuesday 10 May 2011 08:27:42 Helmut Jarausch wrote:
> > On 05/10/2011 02:36:33 AM, Volker Armin Hemmann wrote:
> > > On Sunday 08 May 2011 12:59:57 Helmut Jarausch wrote:
> > > > On 05/08/2011 11:21:06 AM, Florian Philipp wrote:
> > > >
> > > > sys-process/atop shows current CPU freqency
> > > > I use it to check the effect of sys-power/powernowd
> > >
> > > why are you using powernowd?
> >
> > Why not? It's a daemon which reduces the CPU speed under certain
> > circumstances.
>
> just like the kernel. Only the kernel does it better.
>
> > This not only saves power but it reduce the noise produced by the
> fan.
>
> fanspeed - if you have a pwm fan.
>
> Seriously, powernowd is so not needed. Just built a kernel with
> ondemand cpu
> governor. You are done.

Hi,
I've just tried that, but it doesn't work (at least, as the output of
atop is concerned)

dmesg shows
cpuidle: using governor ladder
cpuidle: using governor menu

Am I missing something?

Thanks for a hint,
Helmut.

Check CPU for throttling
 

Am 10.05.2011 16:34, schrieb Helmut Jarausch:

> Am I missing something?

Look at 'grep MHz /proc/cpuinfo' to see if your CPU is throttling
correctly.

Check CPU for throttling
 

On 05/10/2011 04:42:52 PM, Sebastian Beßler wrote:
> Am 10.05.2011 16:34, schrieb Helmut Jarausch:
>
> > Am I missing something?
>
> Look at 'grep MHz /proc/cpuinfo' to see if your CPU is throttling
> correctly.

And that tells me that the CPU is running at full speed (3 GHz in my
case) although all CPUs are idle.

Helmut.