A versatile parallel block-tridiagonal solver for spectral codes
Jungpyo Lee, Wright, John · DSpace@MIT (Massachusetts Institute of Technology) · 2010
Three-dimensional (3-D) processor configuration of a parallel solver is introduced to solve a massive block-tridiagonal matrix system in this paper.The purpose of the added parallelization dimension is to retard the saturation of the scaling due to communication overhead and an inefficient parallelization.The semi-empirical formula for the matrix operation count of the typical parallel algorithms is estimated including the saturation effect in 3-D processor grid.As the most suitable algorithm, the combined method of "Divide-and-Conquer" and "Cyclic Odd-Even Reduction" is implemented in a MPI-Fortran90 based numerical code named TORIC.The new 3-D parallel solver of TORIC using thousands of processors shows about 4 times improved computation speed at the optimized 3-D grid than the old 2-D parallel solver in the same condition.