Scalability of parallel spatial direct numerical simulations on intel hypercube and IBM SP1 and SP2

Abstract

The implementation and performance of a parallel spatial direct numerical simulation (PSDNS) approach on the Intel iPSC/860 hypercube and IBM SP1 and SP2 parallel computers is documented. Spatially evolving disturbances associated with laminar-to-turbulent transition in boundary-layer flows are computed with the PSDNS code. The feasibility of using the PSDNS to perform transition studies on these computers is examined. The results indicate that PSNDS approach can effectively be parallelized on a distributed memory parallel machine by remapping the distributed data structure during the course of the calculation. The performance of the PSDNS indicates that 32 nodes on the IBM SP1 or SP2 are required to match a comparable computation on the CRAY C-90 single processor; the hypercube was found to be two times slower than the CRAY Y/MP for this application.