Abstract

Power dissipation has become one of the most critical factors for the continued development of both high-end and low-end computer systems. The successful design and evaluation of power optimization techniques to address this vital issue is invariably tied to the availability of a broad and accurate set of simulation tools. Existing power simulators are mainly targeted for particular hardware components such as CPU or memory systems and do not capture the interaction between different system components. In this work, we present a complete system power simulator, called SoftWatt, that models the CPU, memory hierarchy and a low-power disk subsystem and quantifies the power behavior of both the application and operating system. This tool, built on top of the SimOS infrastructure, uses validated analytical energy models to identify the power hotspots in the system components, capture relative contributions of the user and kernel code to the system power profile, identify the power-hungry operating system services and characterize the variance in kernel power profile with respect to workload. Our results using Spec JVM98 benchmark suite emphasize the importance of complete system simulation to understand the power impact of architecture and operating system on application execution. 1

Citations