The development of applications and tools for high-performance "computational grids" is complicated by the heterogeneity and frequently dynamic behavior of the underlying resources; by the complexity of the applications themselves, which often combine aspects of supercomputing and distributed computing; and by the need to achieve high levels of performance. The Globus toolkit has been developed with the goal of simplifying this application development task, by providing implementations of various core services deemed essential for high-performance distributed computing. In this paper, we describe two large applications developed with this toolkit: a distributed interactive simulation and a teleimmersion system. We describe the process used to develop the applications, review the lessons learned and draw conclusions regarding the effectiveness of the toolkit approach.

The Tera Multithreaded Architecture (MTA) is a radical new architecture intended to revolutionize high-performance computing in both the scientific and commercial marketplaces. Each processor supports 128 threads in hardware. Extremely fast thread switching is used to mask latency in a uniform-access memory system without caching. It is claimed that these hardware characteristics allow compilers to easily transform sequential programs into efficient multithreaded programs for the Tera MTA. In this paper, we attempt to provide an objective initial evaluation of the performance of the Tera multithreaded architecture and programming system for general-purpose applications. The basis of our investigation is two programs from the C3I Parallel Benchmark Suite (C3IPBS). Both these programs have previously been shown to have the potential for large-scale parallelization. We compare the performance of these programs on (i) a fast uniprocessor, (ii) two conventional shared-memory multiprocessors, and (iii) the first installed Tera MTA (at the San Diego Supercomputer Center). On these platforms, we compare the effectiveness of both automatic and manual parallelization.