Load control and load balancing in a shared database management system

In shared database management systems, there is a need for dynamically setting a large number of operational parameters, like transaction routing tables, assignment of central resources, multiprogramming level, etc. It is shown that static techniques as they are applied in current centralized DBMSs are inadequate for exploiting the performance potential of a shared DBMS. We therefore plead for using dynamic load control methods for adaptive modification of the DBMS´s operational parameters. After a brief survey of the state of the art in database load control, we outline an approach for load balancing in a shared system, which consists of both analytic models and heuristics. The key concepts are illustrated by a simple example, and a number of areas for future research are identified.