DI-GRUBER: A Distributed Approach to Grid Resource Brokering

Managing usage service level agreements (USLAs) within environments that integrate participants and resources spanning multiple physical institutions is a challenging problem. Maintaining a single unified USLA management decision point over hundreds to thousands of jobs and sites can become a bottleneck in terms of reliability as well as performance. DIGRUBER, an extension to our GRUBER brokering framework, was developed as a distributed grid USLAbased resource broker that allows multiple decision points to coexist and cooperate in real-time. DIGRUBER addresses issues regarding how USLAs can be stored, retrieved, and disseminated efficiently in a large distributed environment. The key question this paper addresses is the scalability and performance of DI-GRUBER in large Grid environments. We conclude that as little as three to five decision points can be sufficient in an environment with 300 sites and 60 VOs, an environment ten times larger than today’s Open Science Grid.