The Cydra 5 departmental supercomputer: design philosophies, decisions, and trade-offs

The Cydra 5 is a heterogeneous multiprocessor system that targets small work groups or departments of scientists and engineers. The two types of processors are functionally specialized for the different components of the work load found in a departmental setting. The Cydra 5 numeric processor, based on a directed-data-flow architecture, provides consistently high performance on a broader class of numerical computations. The interactive processors offload all nonnumeric work from the numeric processor, leaving it free to spend all its time on the numeric application. The I/O processors permit high-bandwidth I/O transitions with minimal involvement from the interactive or numeric processors. The system architecture and data-flow architecture are described. The numeric processor decisions and tradeoffs are examined, and the main memory system is discussed. Some reflections on the design issues are offered.< >