Application-based early performance evaluation of SGI altix 4700 systems for SGI systems

The suitability of the next generation of high performance computing systems for petascale simulations will depend on a balance between various factors such as processor performance, memory performance, local and global network performance, and Input/Output (I/O) performance. As the supercomputing industry develops new technologies for these subsystems, achieving system balance becomes challenging. In this paper we evaluate the performance of newly introduced dual-core based SGI Altix 4700 systems (both Bandwidth and Density models) and we compare their performance with that of a single-core based SGI Altix 3700 Bx2 system. The SGI Altix 4700 Density system installed in October 2007 at NASA Ames Research Center is the largest 2048-processor single system image (SSI) system in the world. We used the High Performance Computing Challenge (HPCC) benchmark, NAS Parallel benchmarks (NPB) and five real-world applications, three from computational fluid dynamics, one from climate modeling and one from nanotechnology. Our study shows that the SGI Altix 4700 Bandwidth system performs slightly better and SGI Altix 4700 Density system performs slightly worse than the SGI Altix 3700 Bx2 up to 128 processors, while the performance of the systems is almost the same beyond 128 processors, when the communication time dominates the compute time.