The SB-Tree: An Index-Sequential Structure for High-Performance Sequential Access (1992) [5 citations — 0 self]
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Abstract:
ABSTRACT. A variant of a B-tree known as an SB-tree is introduced, with the object of offering high-performance sequential disk access for long range retrievals. The key to this efficiency is a structure which supports multi-page reads (or writes) during sequential access to any node level below the root, even following significant node splitting. In addition, the SBtree will support a policy to "stripe " successive multi-page blocks on multiple disks to achieve maximum parallelism. Compared to traditional B-tree structures, SB-tree performance characteristics are less subject to degradation resulting from modifications entailed in growing and shrinking; SB-trees are therefore more appropriate for use in situations where frequent reorganization is not possible. A performance analysis reveals the strengths of the SB-tree by comparing its performance under various circumstances to the B-tree and the Bounded Disorder (BD) file of [11]. The performance analysis formulates a new useful concept, the "effective depth " of an SB- or B-tree, defined as the expected number of pages read from disk to perform a random retrieval search given standard buffering behavior. A graph of effective depth against tree size is shown to have a scalloped appearance, reflecting the changing effectiveness of incremental additions to buffer space.
