An E cient Directory System for DocumentRetrieval using Parallel

This paper introduces an eecient le directory structure which provides for parallel retrieval of documents. The directory structure is based on the M-B-T directory structure. The M-B-T directory structure is compatible with current automatic retrieval and query processing techniques. Weights that are assigned to index terms can be included in the directory with the terms at no additional cost. In addition, it provides for indexing a secondary attribute within a primary attribute with no additional cost. Updates are achieved with a high degree of eeciency as well. It is shown that this structure achieves a better overall performance than inverted les, standard B-trees, and other directory structures. The parallel organization of M-B-T directory improves considerably the performance of the directory. Given a p-processor massively parallel computer, our organization allows a maximum of p retrievals to be performed concurrently and thus achieves an approximate speed up of p in the best case.