EXCES: External caching in energy saving storage systems

Power consumption within the disk-based storage subsystem forms a substantial portion of the overall energy footprint in commodity systems. Researchers have proposed external caching on a persistent, low-power storage device, which we term external caching device (ECD), to minimize disk activity and conserve energy. While recent simulationbased studies have argued in favor of this approach, the lack of an actual system implementation has precluded answering several key questions about external caching systems. We present the design and implementation of EXCES, an external caching system that employs prefetching, caching, and buffering of disk data for reducing disk activity. EXCES addresses important questions related to external caching, including the estimation of future data popularity, I/O indirection, continuous reconfiguration of the ECD contents, and data consistency. We evaluated EXCES with both micro- and macro- benchmarks that address idle, I/O intensive, and real-world work...

• Type: Conference
• Year: 2008
• Where: HPCA
• Authors: Luis Useche, Jorge Guerra, Medha Bhadkamkar, Mauricio Alarcon, Raju Rangaswami
• Keywords: Computer Architecture, External Caching, External Caching Device, External Caching Systems, HPCA 2008