Grid middleware needs to adapt to changing resources for a large variety of operations. Currently, however, there is only low-level information available about Grid resources, coming from various but functionally isolated monitoring and information systems. In this paper, we present the Delphoi service. It provides a unified interface to the necessary information, and also matches the abstraction level needed by middleware services to adapt their behavior. We describe Delphoi's architecture, the information it provides, and we evaluate the quality of its performance information. Delphoi has been developed as part of the EC-funded GridLab project and is currently being deployed on the project's testbed for adding adaptivity to GridLab's middleware services. Copyright © 2006 John Wiley & Sons, Ltd.
|Journal||Concurrency and Computation: Practice and Experience|
|Publication status||Published - 2006|