Linear hashing with Priority Splitting: A method for improving the retrieval performance of linear hashing

Abstract

Linear hashing is a technique for constructing dynamic files for direct access. It has an advantage over other dynamic methods in that it lacks a directory. However, a weakness of the method is that at high packing factors, it requires more probes on the average to access a record than do many of the static methods. This paper presents a straightforward modification of linear hashing which, according to experimental results, significantly reduces the average number of retrieval probes in almost aft cases when compared with standard linear hashing. The parameter of overflow page size is an important one for adjusting performance. By choosing an appropriate overflow page size, the user may obtain results which are also better or comparable to those of other variants of linear hashing. In addition, the paper analyzes the effects of varying the primary page size, the overflow page size, and the packing factor on retrieval performance.