Proceedings 17th International Conference on Data Engineering (2001)
Apr. 2, 2001 to Apr. 6, 2001
Uwe Röhm , Swiss Federal Institute of Technology
Klemens Böhm , Swiss Federal Institute of Technology
Hans-Jörg Schek , Swiss Federal Institute of Technology
Abstract: We investigate query routing techniques in a cluster of databases for a query-dominant environment. The objective is to decrease query response time. Each component of the cluster runs an off-the-shelf DBMS and holds a copy of the whole database. The cluster has a coordinator that routes each query to an appropriate component. Considering queries of realistic complexity, e.g., TPC-R, this article addresses the following questions: Can routing benefit from caching effects due to previous queries? Since our components are black-boxes, how can we approximate their cache content? How to route a query, given such cache approximations? To answer these questions, we have developed a cache-aware query router that is based on signature approximations of queries. We report on experimental evaluations with the TPC-R benchmark using our PowerDBdatabase cluster prototype. Our main result is that our approach of cache approximation routing is better than state-of-the-art strategies by a factor of two with regard to mean response time.
U. Röhm, K. Böhm and H. Schek, "Cache-Aware Query Routing in a Cluster of Databases," Proceedings 17th International Conference on Data Engineering(ICDE), Heidelberg, Germany, 2001, pp. 0641.