Fast estimation of software energy consumption using IPI(Inter-Prefetch Interval) energy model

In this paper, we present the way of fast and accurate estimation of software energy consumption in off-the-shelf pro- cessor using IPI(Inter-Prefetch Interval) energy model. In our previous work[1], we proposed a new energy estimation method, and presented the way to characterize IPI energy model. However, there were some drawbacks in our previous work. First, the previous IPI energy model was only able to cover basic block. Second, it took too much time to estimate energy consumption of software due to the absence of energy estimator. To tackle these problems, in this paper, we propose modified IPI energy model, and present the way to implement IPI energy estimator using off-the-shelf system-level simulator. By using this, we can analyze such dynamic effect as address jump due to branch instructions and stalls due to hazard fast and accurately. The major challenging issue when implementing IPI energy estimator is cycle-by-cycle behavioral discrepancy between physical chip and ISS(Instruction Set Simulator) in system-level simulator. In order to overcome this problem, we propose training method to reduce the discrepancy. To verify our method, we applied our idea to ARM1136JF-S real chip. By the result of this work, the accuracy of energy estimation is more than 90% compared to measured data on prototyping board.