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Title: Multitasking the Davidson algorithm for the large, sparse eigenvalue problem

Journal Article · · International Journal of Supercomputer Application; (USA)
;  [1]
  1. Vanderbilt Univ., Nashville, TN (USA)

The authors report how the Davidson algorithm, developed for handling the eigenvalue problem for large and sparse matrices arising in quantum chemistry, was modified for use in atomic structure calculations. To date these calculations have used traditional eigenvalue methods, which limit the range of feasible calculations because of their excessive memory requirements and unsatisfactory performance attributed to time-consuming and costly processing of zero valued elements. The replacement of a traditional matrix eigenvalue method by the Davidson algorithm reduced these limitations. Significant speedup was found, which varied with the size of the underlying problem and its sparsity. Furthermore, the range of matrix sizes that can be manipulated efficiently was expended by more than one order or magnitude. On the CRAY X-MP the code was vectorized and the importance of gather/scatter analyzed. A parallelized version of the algorithm obtained an additional 35% reduction in execution time. Speedup due to vectorization and concurrency was also measured on the Alliant FX/8.

OSTI ID:
7128959
Journal Information:
International Journal of Supercomputer Application; (USA), Vol. 3:4; ISSN 0890-2720
Country of Publication:
United States
Language:
English