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We report the computational advances that have enabled the first micron-scale simulation of a Kelvin-Helmholtz (KH) instability using molecular dynamics (MD). The advances are in three key areas for massively parallel computation such as on BlueGene/L (BG/L): fault tolerance, application kernel optimization, and highly efficient parallel I/O. In particular,(More)
We investigate solidification in tantalum and uranium systems ranging in size from 64,000 to 524,288,000 atoms on the IBM BlueGene/L computer at LLNL. Using the newly developed ddcMD code, we achieve performance rates as high as 103 TFlops, with a performance of 101.7 TFlop sustained over a 7 hour run on 131,072 cpus. We demonstrate superb strong and weak(More)
With supercomputers anticipated to expand from thousands to millions of cores, one of the challenges facing scientists is how to effectively utilize this ever-increasing number. We report here an approach that creates a heterogeneous decomposition by partitioning effort according to the scaling properties of the component algorithms. We demonstrate our(More)
Blue Gene/L represents a new way to build supercomputers, using a large number of low power processors, together with multiple integrated interconnection networks. Whether real applications can scale to tens of thousands of processors (on a machine like Blue Gene/L) has been an open question. In this paper, we describe early experience with several physics(More)
We have developed a highly efficient and scalable cardiac electrophysiology simulation capability that supports groundbreaking resolution and detail to elucidate the mechanisms of sudden cardiac death from arrhythmia. We can simulate thousands of heartbeats at a resolution of 0.1 mm, comparable to the size of cardiac cells, thereby enabling scientific(More)
—We have investigated the performance characteristics of hardware transactional memory (HTM) on the BlueGene/Q computer in comparison with conventional concurrency control mechanisms, using a molecular dynamics application as an example. Benchmark tests, along with overhead-cost and scalability analysis, quantify relative performance advantages of HTM over(More)
We propose and analyze threading algorithms for hybrid MPI/OpenMP parallelization of a molecular-dynamics simulation, which are scalable on large multicore clusters. Two data-privatization thread scheduling algorithms via nucleation-growth allocation are introduced: (1) compact-volume allocation scheduling (CVAS); and (2) breadth-first allocation scheduling(More)
— Calculation of the Coulomb potential in the molecular dynamics code ddcMD has been parallelized based on a hybrid MPI/OpenMP scheme. The explicit pair kernel of the particle-particle/particle-mesh algorithm is multi-threaded using OpenMP, while communication between multicore nodes is handled by MPI. We have designed a load balancing spanning forest(More)