Morning Session: Petaflop challenges

From ALPS
Jump to: navigation, search
  • Speaker&Chair: Thomas A. Maier "Petscale Computing"
  • Discussions on talk
    • Ten years from now: will technical aspects of petaflop computing be standardized?
      • High diversity of algorithms/methods prevents standardization
      • Large teams from different fields are required and actually growing over time
      • Speedup of machines comes at a price of more complicated machines
      • Even now, some applications are not run at teraflop scale
    • Is there always a way to do in-situ data analysis?
      • Filesystems scales to a few hundred nodes at most, even with HDF5
      • Use small runs to explore physics, large-scale runs for big systems when questions are clear
    • Is any method besides petaflop currently living on teraflop?
      • Series expansion: possible
      • Exact diagonalization: has been done
        • Depends on Hamiltonian and geometry
        • Use of symmetries
        • Often O(N^2) communication tasks
      • Tensor network states
        • Terascale possible, petaflop still open
        • Difficult linear algebra operations
      • DMRG
        • Many small matrices, high impact of communication latency
        • Shared-memory very easy & efficient: linear scaling
        • Huge matrix-matrix multiply
        • Using GPUs can help a lot
    • Which fields get most FLOPs at Oakridge?
      • Material science, BEC
      • Industry projects: BOEING
      • Climate