In this paper we describe general software utilities for performing unstructured sparse matrixvector multiplications on distributed-memory message-passing computers. The matrix-vector multiply comprises an important kernel in the solution of large sparse linear systems by iterative methods. Our focu
Parallelization Techniques for Sparse Matrix Applications
✍ Scribed by Manuel Ujaldón; Emilio L. Zapata; Shamik D. Sharma; Joel Saltz
- Publisher
- Elsevier Science
- Year
- 1996
- Tongue
- English
- Weight
- 390 KB
- Volume
- 38
- Category
- Article
- ISSN
- 0743-7315
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✦ Synopsis
Sparse matrix problems are difficult to parallelize efficiently on distributed memory machines since data is often accessed indirectly. Inspector-executor strategies, which are typically used to parallelize loops with indirect references, incur substantial runtime preprocessing overheads when references with multiple levels of indirection are encountered-a frequent occurrence in sparse matrix algorithms. The sparse-array rolling (SAR) technique, introduced in [M. Ujaldo ´n and E. L. Zapata, Proc. 9th ACM Int'l. Conf. on Supercomputing, Barcelona, July 1995, pp. 117-126], significantly reduces these preprocessing overheads. This paper outlines the SAR approach and describes its runtime support accompanied by a detailed performance evaluation. The results demonstrate that SAR yields significant reduction in preprocessing overheads compared to standard inspector-executor techniques.
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