Ultra compact, quadratic power proxies for multi-core processors

Per-core power proxies for multi-core processors are known to use more than 40 hardware activity monitors to achieve a 2% accuracy on core power estimation. These activity monitors are typically not accessible by the user, and even if they were accessible, there is a significant overhead in using them at the kernel or OS level for power monitoring or control. Furthermore, when scaled up to hundreds of cores per chip, such power proxies become a computational bottleneck for power management operations such as chip power capping. In this paper, we show that a 4% accuracy or better for per-core power estimation can be achieved using a power proxy based on a hybrid set of only four user-accessible parameters, namely core frequency, core temperature, instruction-per-cycle and active-state residency. We illustrate the accuracy of the model using the full suite of the SPEC CPU 2006 benchmarks on a 12-core processor.