Compilation Techniques for Out-of-Core Parallel Computations

The difficulty of handling out-of-core data limits the performance of supercomputers as well as the potential of the parallel machines. Since writing an efficient out-of-core version of a program is a difficult task and virtual memory systems do not perform well on scientific computations, we believe that there is a clear need for compiler directed explicit I/O approach for out-of-core computations. In this paper, we first present an out-of-core compilation strategy based on a disk storage abstraction. Then we offer a compiler algorithm to optimize locality of disk accesses in out-ofcore codes by choosing a good combination of file layouts on disks and loop transformations. We introduce memory coefficient and processor coefficient concepts to characterize the behavior of out-of-core programs under different memory constraints. We also enhance our algorithm to handle data-parallel programs which contain multiple loop nest. Our initial experimental results obtained on IBM SP-2 and Intel ..

Compilation Techniques for Out-of-Core Parallel Computations

Louisiana Board of Regents through contract LEQSF (1991-94)-RD-A-09