New parallel signature file method for efficient information retrieval

The signature file method has been widely advocated as an efficient index scheme to handle new applications demanding a large volume of textual databases. Moreover, it has recently been extended to support multimedia data. In order to achieve good performance when handling multimedia data, the signature file approach has been required to support parallel database processing. Therefore, in this paper we propose a horizontally-divided parallel signature file (HPSF) method using extendible hashing and frame-slicing techniques. In addition, we also propose a heuristic processor allocation method so that we may assign a set of signatures to a given number of processors in a uniform way. To show the efficiency of HPSF, we evaluate the performance of HPSF in terms of retrieval time, insertion time, and storage overhead. Finally, we show from the performance results that HPSF outperforms the conventional parallel signature file methods regarding retrieval performance and dynamic operating measures used to combine both retrieval and insertion time.