dos33fsprogs/presenter_demo/slide_15_rapl_accuracy

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2012-05-11 03:59:02 +00:00
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%c%RAPL Measurement Accuracy
* Intel Documentation indicates Energy
readings are updated roughly every
millisecond (1kHz)
* The hardware also reports measurement
quanta. This can vary among processor
releases. On our Sandybridge EP all
Energy measurements are in multiples
of 15.2nJ
* Power and Energy can vary between
identical packages on a system,
even when running identical workloads.
It is unclear whether this is due to
process variation or else calibration