Live Webcast 15th Annual Charm++ Workshop

Many important problems in material science, chemistry, solid-state physics, and biophysics require a modeling approach based on fundamental quantum mechanical principles. A particular approach that has proved to be relatively efficient and useful is {\em Car-Parrinello ab initio molecular dynamics} (CPAIMD). Parallelization of this approach beyond a few hundred processors is challenging, due to the complex dependencies among various subcomputations, which lead to complex communication optimization and load balancing problems. We present a scalable parallelization of CPAIMD using. The computation is modeled using a large number of virtual processors, which are mapped flexibly to available processors with assistance from the runtime system. We present results for a benchmark with 32 water molecules (128 states) scaling to more than 1000 processors, setting a precedent for this problem.