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Chemistry; NWChem is an ab initio computational chemistry software package which also includes quantum chemical and molecular dynamics functionality.









From a talk in the KNL workshop at ISC2017, the following characteristics of NWChem were highlighted:






* Heavy on FFT & DGEMM (tall and skinny matrices)



* Strong scaling is Key



* Difficult 3D FFT that scales to 2K nodes



* 3D FFT: 1D FFT + rotate cube + 1D FFT + rotate cube + 1D FFT



* Asynchronous MPI (overlap comp, comm) + threading for 1D FFTs



* MKL deem perf or Tall and Skinny matrix is bad, they do threading themselves and use single threaded MKL dgemm



* One MPI per node and then OpenMP 