Optimistic Concurrency Control for Inverted Files in Text Databases
نویسنده
چکیده
Inverted files are frequently used as index data structures for very large text databases. Most applications of this data structure are for read-only query operations. However, the problem of introducing update operations has deserved little attention so far and yet it has important applications. In this paper we propose an optimistic concurrency control algorithm devised to handle mixes of update operations and read-only queries efficiently. We work on top of the BSP model of parallel computing and take advantage of a BSP Time Warp realization to formulate the proposed algorithm. We present a comparison with the traditional lock-based approach and the results show that optimism is particularly efficient in this case.
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