Issue No. 01 - January (2011 vol. 60)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TC.2010.206
Dan Feng , Huazhong University of Science and Technology, Wuhan
Hong Jiang , University of Nebraska-Lincoln, Lincoln
Suzhen Wu , Huazhong University of Science and Technology, Wuhan and Xiamen University, Xiamen
Lei Tian , Huazhong University of Science and Technology, Wuhan and University of Nebraska-Lincoln, Lincoln
Bo Mao , Huazhong University of Science and Technology, Wuhan
Due to the contention for the shared disk bandwidth, the user I/O intensity can significantly impact the performance of the online low-priority background tasks, thus reducing the reliability and availability of RAID-structured storage systems. In this paper, we propose a novel and practical scheme, called WorkOut (I/O Workload Outsourcing), to significantly boost the performance of those low-priority background tasks. WorkOut effectively outsources all write requests and popular read requests originally targeted at the degraded RAID set that is performing the low-priority background tasks to a surrogate RAID set. The lightweight prototype implementation of WorkOut and extensive trace-driven and benchmark-driven experiments on two case studies demonstrate that, compared with existing approaches, WorkOut effectively improves the performance of the low-priority background tasks, such as RAID reconstruction and RAID resynchronization. Importantly, WorkOut is portable and can be easily incorporated into any existing optimizing algorithms for RAID-structured storage systems.
Low-priority background tasks, RAID reconstruction, reliability, availability, performance evaluation.
Dan Feng, Hong Jiang, Suzhen Wu, Lei Tian, Bo Mao, "Improving Availability of RAID-Structured Storage Systems by Workload Outsourcing", IEEE Transactions on Computers, vol. 60, no. , pp. 64-79, January 2011, doi:10.1109/TC.2010.206