Watts-inside: A hardware-software cooperative approach for Multicore Power Debugging

Multicore computing presents unique challenges for performance and power optimizations due to the multiplicity of cores and the complexity of interactions between the hardware resources. Understanding multicore power and its implications on application behavior is critical to the future of multicore software development. In this paper, we propose Watts-inside, a hardware-software cooperative framework that relies on the efficiency of hardware support to accurately gather application power profiles, and utilizes software support and causation principles for a more comprehensive understanding of application power. We show the design of our framework, along with certain optimizations that increase the ease of implementation. We present a case study using two real applications, Ocean (Splash-2) and Streamcluster (Parsec-1.0) where, with the help of feedback from Watts-inside framework, we made simple code modifications and realized up to 5% power savings on chip power consumption.