Automatic generation of efficient array redistribution routines for distributed memory multicomputers

Appropriate data distribution has been found to be critical for obtaining good performance on Distributed Memory Multicomputers like the CM-5, Intel Paragon and IBM SP-1. It has also been found that some programs need to change their distributions during execution for better performance (redistribution). This work focuses on automatically generating efficient routines for redistribution. We present a new mathematical representation for regular distributions called PITFALLS and then discuss algorithms for redistribution based on this representation. A significant contribution of this work is the ability to handle arbitrary source and target processor sets while performing redistribution; another is the ability to handle arbitrary dimensionality for the array being redistributed in a sealable manner. The results presented show low overheads for our redistribution algorithm as compared to naive runtime methods