Modern, resource-intensive enterprise and scientific applications are increasingly architected using parallel and distributed components deployed on grid platforms. Grid environments are typically heterogeneous and subject to large load variations. Such characteristics require a portable programming infrastructure and comprehensive support for resource management as well as dynamic adaptation to varying resource availability. Resource-aware applications pro-actively monitor and dynamically adapt their behavior to accommodate to changing resource consumption constraints. Strategies such as internal load-balancing and job re-submission can correct sub-optimal scheduling decisions and thus enhance performance. As utilizing the potential of resource awareness requires close interaction with resource management subsystems, implementations often rely on low-level, platform-specific features, which impair portability. What is needed is uncompromised portability of all aspects of resource management in grid systems. We demonstrate that the Java platform, equipped with the APIs for distributed resource management, can be used for building a portable grid infrastructure. In particular, we describe the design and implementation of a cluster management system capable of controlled execution of parallel, resource-aware Java applications. We empirically show that our solution allows for efficient, fine-grained resource management, sufficient for tapping the performance benefits promised by the resource-conscious applications.

Enterprise applications are increasingly being built using type-safe programming platforms and deployed over horizontally scalable systems. Horizontal scalability depends crucially on the ability to monitor resource usage and to define and enforce resource management policies capable of guaranteeing a desired service level. However, current safe language platforms have very limited support for resource management, and their cluster-enabled versions reflect this deficiency. We describe an architecture of federated Java/spl trade/ virtual machines. Its distinguishing feature is an integrated resource management interface that addresses the above issues. It offers programmatic control over monitoring and controlling the allocation of resources to applications and their components. The scope of each policy can span multiple nodes, realizing finegrained control. New resource types can be defined and integrated into the framework. Remote management of local resources and the notion of cluster-global resources form a powerful combination capable of expressing policies that achieve effective performance isolation for cluster applications.

Executing computations in a single instance of safe language virtual machine can improve performance and overall platform scalability. It also poses various challenges. One of them is providing a fast inter-application communication mechanism. In addition to being efficient, such a mechanism should not violate any functional and non-functional properties of its environment, and should also support enforcement of application-specific security policies. This paper explores the design and implementation of a communication substrate for applications executing within a single Java virtual machine modified to enable safe and interference-free execution of isolated computations. Designing an efficient extension that does not break isolation properties and at the same time pragmatically offers an intuitive API has proven non-trivial. This paper demonstrates a set of techniques that lead to at least an eight-fold performance improvement over the in-process inter-application communication using standard mechanisms offered by the Java platform.