Optimizing Power using Reconfigurable Middleware

In distributed environments, generic middleware services(e.g. caching, location management etc.) are widely used to satisfy application needs in a cost-effective manner. Such middleware services consume system resources such as storage, computation and communication and can be sources of significant power overheads when executed on low-power devices. Our goal is to develop a distributed middleware framework that is inherently power-aware and reconfigures itself to adapt to diminishing power levels of low-power devices in distributed systems. This paper presents and evaluates a methodology for optimizing the power consumption of low-power devices using a reflective and customizable middleware framework. It introduces a power-aware middleware framework (parm) and identifies some of the intrinsic requirements for the framework to be effective. Specifically, we determine when middleware components can be dynamically stopped or migrated away from a low-power device operating, in order to maximize the remaining service time for the device. In this paper, we 1) determine whether a reconfigurable component-based middleware framework can be utilized to achieve energy gains on lowpower devices in distributed environments, while preserving the semantics of the middleware services, 2) design and evaluate a graph theoretic approach for dynamically determining middleware component reconfigurations, and ascertaining the optimal frequency at which the restructuring should take place, for maximal energy and service time gains at the device. We use extensive profiling to chart the energy usage patterns of middleware components and applications, and use the profiled data to drive our reconfiguration decisions. Our extensive simulation results demonstrate that our framework is able to save 5% to 45% of energy depending on the nature and class of applications and middleware components used.