High-Performance Commodity Computing

In this chapter, we consider the role of commodity off-the-shelf software technologies and components in the construction of computational grids. We take the position that computational grids can and should build on emerging commodity network computing technologies, such as the CORBA, COM, JavaBeans, and less sophisticated Web and networked approaches. These technologies are being used to construct three-tier architectures, in which middle-tier application servers mediate between sophisticated back-end services and potentially simple front ends. The decomposition of application functionality into separate presentation, application, and back-end service tiers results in a distributed computing architecture that can be extended transparently to incorporate grid-enabled second-and/or third-tier services. Consequently, the three-tier architecture being deployed for commodity network applications is well suited to serve as an architecture for computational grids, combining high performance with the rich functionality of commodity systems. The distinct interface, server, and specialized service implementation layers enable technological advances to be incorporated in an incremental fashion. This commodity approach to grid architecture should be contrasted with more specialized grid architectures such as Globus (Chapter 11) and Legion (Chapter 9). Clearly, these latter technologies can be used to implement lower-tier services. This would seem to be particularly consistent with the Globus service-oriented approach to grid computing. The rest of this chapter proceeds as follows. We first define what we mean by " commodity technologies " and explain the different ways that they can be used in high-performance computing. Then, we discuss an emerging