measuring avg cpu speed while powerd(8) is running

Philip S. Schulz ph.schulz at gmx.de
Sun Aug 7 18:39:42 GMT 2005


Joost Bekkers wrote:
> On Sat, Aug 06, 2005 at 07:33:02PM +0200, Philip S. Schulz wrote:
> 
>>Joost Bekkers wrote:
>>
>>>Is there a way to calculate (over eg. a 5 minute interval) the average 
>>>amount the cpu was throttled? In this case by powerd(8).
>>
[...]
> 
> Perhaps I should have said that differently: it is being throttled by powerd.
> It doesn't have to do the measuring of the average itself.
> 

So you're looking for a history of the CPU frequency, similar to the 
history of CPU usage? I don't think the kernel keeps any such 
statistics. But you should take a look at the man page or possibly the 
sources of the driver you're using, e.g. est or powernow.

> 
>>>I was thinking there might be a counter/timer which is linked to the cpu 
>>>clock, but sofar I haven't been able to find one.
>>
>>Well, you can see the current CPU frequency by looking at dev.cpu.0.freq 
>>where 0 is the id of the CPU you want to query.
> 
> At the times I take measurements the cpu tends to run at 100%, which would
> result in a nice flat line.
> 

I don't really understand what you mean. What problem are you trying to 
solve?



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