In this paper we report on features added to a parallel debugger to simplify the debugging of message passing programs. These features include replay, setting consistent breakpoints based on interprocess event causality, a parallel undo operation, and communication supervision. These features all use trace information collected during the execution of the program being debugged. We used a numbe...

We present a fast and memory efficient algorithm that generates a manifold triangular mesh S passing through a set of unorganized points P ‰ R3. Nothing is assumed about the geometry, topology or presence of boundaries in the data set except that P is sampled from a real manifold surface. The speed of our algorithm is derived from a projection-based approach we use to determine the incident fac...

Benchmarks of our “production” codes show that Pentium-based multi-processors computers running the Linux operating system are attractive options for SEP’s next computational server(s). A four-processor SGI 1400 L (500 Mhz Pentium III Xeon) has consistently performed as well as, or better than, our SGI Origin 200 (180 Mhz R10000). We used the Portland Group’s pgf90 compiler to compile our bench...

The HPC Challenge (HPCC) benchmark suite and the Intel MPI Benchmark (IMB) are used to compare and evaluate the combined performance of processor, memory subsystem and interconnect fabric of six leading supercomputers SGI Altix BX2, Cray X1, Cray Opteron Cluster, Dell Xeon cluster, NEC SX-8, Cray XT3 and IBM Blue Gene/L. These six systems use also six different networks (SGI NUMALINK4, Cray net...

The HPC Challenge (HPCC) benchmark suite and the Intel MPI Benchmark (IMB) are used to compare and evaluate the combined performance of processor, memory subsystem and interconnect fabric of six leading supercomputers SGI Altix BX2, Cray X1, Cray Opteron Cluster, Dell Xeon cluster, NEC SX-8 and IBM Blue Gene/L. These six systems use also six different networks (SGI NUMALINK4, Cray network, Myri...

POSIX Threads and OpenMP were used to implement parallelism in the nuclear reactor transient analysis code PARCS on multiprocessor SUN and SGI workstations. The achievable parallel performance for practical applications is compared for each of the code modules using POSIX threads and OpenMP. A detailed analysis of the cache misses was performed on the SGI to explain the observed performance. Co...

The parallel numerical solution of large scale elliptic boundary value problems is discussed. We analyze the parallel complexity of two block-circulant preconditioners when the conjugate gradient method is used to solve the sparse linear systems arising from such problems. A simple general model of the parallel performance is applied to the considered shared memory parallel architecture. Estima...