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%c%How RAPL Works

* RAPL is not an analog power meter

* RAPL uses a software power model, 
  running on a helper controller
  on the main chip package

* Energy is estimated using various 
  hardware performance counters, 
  temperature, leakage models and I/O

* The model is used for CPU throttling
  and turbo-boost, but the values are 
  also exposed to users via a 
  model-specific register (MSR)