Execution time support for adaptive scientific algorithms on distributed memory machines,” Concurrency: Practice and Experience

We consider optimizations that are required for efficient execution of code segments that consists of loops over distributed data structures. The PARTI A execution time primitives are designed to carry out these optimizations and' can be used to implement a wide range of scientific algorithms on distributed memory machines. These primitives allow the user to control array mappings in a way that gives an appearance of shared memory. Computations can be based on a global index set. Primitives are used to carry out gather and scatter operations on distributed arrays. Communications patterns are derived at runtime, and the appropriate send and receive messages are automatically generated. i Aocession For NTIS GRA&