A Performance Comparison Through Benchmarking and Modeling of Three Leading Supercomputers: Blue Gene/L, Red Storm, and Purple

This work provides a performance analysis of three leading supercomputers that have recently been deployed: Purple, Red Storm and Blue Gene/L. Each of these machines is architecturally diverse, with very different performance characteristics. Each contains over 10,000 processors and has a system peak of over 40 Teraflops. We analyze each system using a range of micro-benchmarks which include communication performance as well as quantifying the impact of the operating system. The achievable application performance is compared across the systems. The application performance is confirmed via the use of detailed application models which use the underlying performance characteristics as measured by the micro-benchmarks. We also compare the machines in a realistic production scenario in which each machine is used so as to maximize its memory usage with the applications executed in a weak-scaling mode. The results also help illustrate that achievable performance is not directly related to the peak performance