Implementation and evaluation of a parallel text searcher for very large text databases

The Utah Retrieval System Architecture (URSA) was initially developed in 1981 developed as an alternative to central-processor-based information retrieval systems. It combined distributed processing and a windowed user interface with a hardware-based search server combined with using document surrogates such as partially-inverted files. The authors have now started the development and testing of a medium-scale (about 10 gigabyte) parallel backend search server to demonstrate its operation and to gather data on the use of such a backend processor in actual operation, including information about query complexity and arrival rates. This searcher, based on a hardware-augmented RISC processor, builds on their experience developing and operating the custom VLSI FSA-based search engine. The use of a programmable processor allows the easy implementation of complex search patterns, such as numeric range matching, while the special hardware augmentation provides considerably better performance than would be available from a standard RISC processor server