A Hybrid Distributed Architecture for Indexing

This paper presents a hybrid scavenger grid as an underlying hardware architecture for search services within digital libraries. The hybrid scavenger grid consists of both dedicated servers and dynamic resources in the form of idle workstations to handle mediumto large-scale search engine workloads. The dedicated resources are expected to have reliable and predictable behaviour. The dynamic resources are used opportunistically without any guarantees of availability. Test results confirmed that indexing performance is directly related to the size of the hybrid grid and intranet networking does not play a major role. A systemefficiency and cost-effectiveness comparison of a grid and a multiprocessor machine showed that for workloads of modest to large sizes, the grid architecture delivers better throughput per unit cost than themultiprocessor, at a system efficiency that is comparable to that of the multiprocessor.