Enabling accurate and efficient modeling-based CPU power estimation for smartphones

CPU is one of the most significant sources of power consumption on smartphones. Power modeling is a key technique and important tool for power estimation and management, both of which are critical for providing good QoS for smartphones. However, we find that existing CPU power models for smartphones are ill-suited for modern multicore CPUs: they can give high estimation errors (up to 34%) and high estimation accuracy variation (more than 30%) for different types of workloads on mainstream multicore smartphones. The cause is that the existing approaches do not appropriately consider the effects of CPU idle power states on smartphones CPU power modeling. Based on our extensive measurement experiments, we develop a new CPU power modeling approach that carefully considers the effects of CPU idle power states. We present the detailed design of our power modeling approach, and a prototype CPU power estimation system on commercial multicore smartphones. Evaluation results show that our approach consistently achieves higher power estimation accuracy and stability for various benchmarks programs and real apps than the existing approaches.