GPAW

• Cython program

  • Pros and Cons of Hybrid MPI/OMP
  • 70% runtime in C, 30% runtime in Python

• Computation intense program

  • Highly depend on Math library

• Hybrid MPI/OpenMP program

  • Pros and Cons of Hybrid MPI/OMP
  • Balance of MPI/OpenMP

GPU Accelerated

• ELPA
  • A highly efficient and highly scalable direct eigensolvers for symmetrix(hermitian) matrices.
  • with this math library, the performance can increase 3x-5x.

Profiling

• Accroding to the IPM Profile information, we figure out that MPI_Allredce is the most time comsuming.
  • We have tried profile the ratio of MPI and OpenMP since it is a Hybird MPI/OpenMP program, but the performance is unstable since different python use gpaw may have different calculate routines.

Lesson Learned

• Python GIL Lock sometimes make profile difficult.

• Cython program usually have time cosuming part at C code, optimize this part.

• Some General Math Library (such as MKL) may not help a lot with specific program, but some minor specific Library will.