BetaBetaReturns the estimate of the value (in units, as value during sampling)
For example, if the value is throughput (in bits per seconds), the estimate will also be in bits per seconds.
BetaReturns the total duration of the resource (in units, as weight during sampling)
BetaSamples the value of the resource and updates the estimate.
Exponential Weighted Moving Average (EWMA)