Early performance results on the NRL SGI Altix 3000 computer

Since December 2002 the Naval Research Laboratory (NRL) has been evaluating an Altix 3000, the newest high performance computing system available from Silicon Graphics, Inc. (SGI). The Altix is a departure from the previous products from SGI in that instead of using MIPS processors and the IRIX operating system, the Altix uses the Intel Itanium IA-64 processor and SGI ProPack (based on Linux Red Hat) operating system. The Altix still has the brick concept of system configuration and the SGI NUMAlink for the inter-module network for the shared memory. The Altix runs under a single image of the operating system and supports parallel programming through OpenMP, MPI, CoArray, FORTRAN, and an automatic parallelizing compiler. Various codes have been evaluated with respect to their ease of portability and their performance on the Altix as compared to other high performance computers.