Energy Efficient Prefetching with Buffer Disks for Cluster File Systems

Energy efficient computing is becoming increasingly important as the scale of parallel computing systems is expanding. As the processing power of parallel computing systems has been incremented there has been an increased demand for large scale storage systems to store the output of these parallel computing systems. Data centers are growing at an enormous pace and it is important to investigate a means of managing the energy efficiency of large scale parallel storage systems. To address these issues we introduce EEVFS (Energy Efficient Virtual File System), which is able to manage data placement and disk states to help improve the energy efficiency of a parallel disk system. EEVFS places data on the storage disks in an energy efficient layout and attempts to predict when each disk will be idle for a large period of time, facilitating a state transition into the standby state. EEVFS should also maintain relatively high performance, so we have built a load balancing policy into the data partitioning of EEVFS. The implementation architecture and measured results are presented to demonstrate the energy efficiency and performance characteristics of EEVFS.