A systematic method for functional unit power estimation in microprocessors

We present a new method for mathematically estimating the active unit power of functional units in modern microprocessors such as the Pentium 4 family. Our method leverages the phasic behavior in power consumption of programs, and captures as many power phases as possible to form a linear system of equations such that the functional unit power can be solved. Our experiment results on a real Pentium 4 processor show that power estimations attained as such agree with the measured power very well, with deviations less than 5% only.