Design theoretic approach to replicated declustering

Declustering techniques reduce query response times through parallel I/O by distributing data among multiple devices. Most of the research on declustering is targeted at spatial range queries and investigates schemes with low additive error. Recently, declustering using replication is proposed to reduce the additive overhead. Replication significantly reduces retrieval cost of arbitrary queries. In this paper, we propose a disk allocation and retrieval mechanism for arbitrary queries based on design theory. Using proposed c-copy replicated declustering scheme, (c - 1)k/sup 2/ + ck buckets can be retrieved using at most k disk accesses. Retrieval algorithm is very efficient and is asymptotically optimal with /spl Theta/(|Q|) complexity for a query Q. In addition to the deterministic worst-case bound and efficient retrieval, proposed algorithm handles nonuniform data, high dimensions, supports incremental declustering and has good fault-tolerance property.