Declustered disk array architectures with optimal and near-optimal parallelism

摘要: This paper investigates the placement of data and parity on redundant disk arrays. Declustered organizations have been traditionally used to achieve fast reconstruction a failed disk's contents. In previous work, Holland Gibson identified six desirable properties for ideal layouts; however, no declustered layout satisfying all has published in literature. We present complete, constructive characterization collection layouts possessing properties. Given that exist only limited set configurations, we also two novel families. PRIME RELPR can tolerate multiple failures wide variety configurations with slight deviations from ideal. Our simulation studies show new provide excellent parallel access performance reduced incremental loads during degraded operation, when compared previously layouts. For large accesses under high loads, response times are typically smaller than those by factor 2.5.