Issue No.01 - January (2002 vol.13)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/71.980025
<p>This paper presents a new distributed disk-array architecture for achieving high I/O performance in scalable cluster computing. In a serverless cluster of computers, all distributed local disks can be integrated as a <it>distributed-software redundant array of independent disks </it>(ds-RAID) with a single I/O space. We report the new RAID-x design and its benchmark performance results. The advantage of RAID-x comes mainly from its <it>orthogonal striping </it>and<it> mirroring</it> (OSM) architecture. The bandwidth is enhanced with distributed striping across local and remote disks, while the reliability comes from orthogonal mirroring on local disks at the background. Our RAID-x design is experimentally compared with the RAID-5, RAID-10, and chained-declustering RAID through benchmarking on a research Linux cluster at USC. Andrew and Bonnie benchmark results are reported on all four disk-array architectures. Cooperative disk drivers and Linux extensions are developed to enable not only the single I/O space, but also the shared virtual memory and global file hierarchy. We reveal the effects of traffic rate and stripe unit size on I/O performance. Through scalability and overhead analysis, we find the strength of RAID-x in three areas: 1) improved aggregate I/O bandwidth especially for parallel writes, 2) orthogonal mirroring with low software overhead, and 3) enhanced scalability in cluster I/O processing. Architectural strengths and weakness of all four ds-RAID architectures are evaluated comparatively. The optimal choice among them depends on parallel read/write performance desired, the level of fault tolerance required, and the cost-effectiveness in specific I/O processing applications.</p>
Distributed computing, parallel I/O, software RAID, single I/O space, Linux clusters, fault tolerance, Andrew and Bonnie benchmarks, network file servers, scalability and overhead analysis.
Kai Hwang, Hai Jin, Roy S.C. Ho, "Orthogonal Striping and Mirroring in Distributed RAID for I/O-Centric Cluster Computing", IEEE Transactions on Parallel & Distributed Systems, vol.13, no. 1, pp. 26-44, January 2002, doi:10.1109/71.980025