Consistent performance
Our Physon (in Bulgarian only) HPC1 cluster was originally composed of four dual Xeon mobos with QDR (20 Gbps) InfiniBand links as interconnection fabric for MPI2 message passing. Armed with eight quad-core Xeon E5335 (2,0 GHz, 2x4 MB L2 cache) the system peaked at Rmax equal to 209,0 GFLOPS for Nmax of 74880 on the High Performance LINPACK (HPL) test. Since the theoretical top performance is Rpeak equal to 256 GFLOPS, our old nodes have parallel efficiency of 0,816.