Software Tuning, Performance Optimization & Platform Monitoring
Discussion regarding monitoring and software tuning methodologies, Performance Monitoring Unit (PMU) of Intel microprocessors, and platform updating.
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Intel PCM: How to convert energy to power ?? Very low Energy Measurements




I am using Intel PCM to measure the dynamic power consumed on Intel Sandybrige platform. What it gives me is an Energy Value in Joules.  Is it true that this values is updated every second ?

If so, how to convert this energy value into Power in Watts ??

Will this method be true??

    As Power = Energy/Time

For a reported energy of 2 Joules which is typically reported for my Laptop when just running OS and the Browser , the power estimate will be 

         Power = 2 Joules/ 1 s = 2W 

This seems very odd for a processor to report this low dynamic power 

Can I know what is correct method to read power using Intel PCM ??



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Hi, PCM reports energy values in Joules between the measurements. If you run it is "pcm.exe 1" then the delay between the measurements is 1 second. In such a case the output value will correspond to power in Watt (=Joule/second). Are you measuring the processor power this way? If the OS and other applications not doing active processing (for example when you just read the content of already loaded web page) the processor can go into a low power state significantly reducing energy consumption. Could you provide more detail on your processor (model number, etc). This processor information is output by pcm.exe in the beginning : "Detected ... Intel(r) microarchitecture codename ...". Best regards, Roman
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