Spi Alignment and Distribution Is Not (always) Np-hard Alignment and Distribution Is Not (always) Np-hard Alignment and Distribution Is Not (always) Np-hard
نویسندگان
چکیده
In this paper, an eecient algorithm to simultaneously implement array alignment and data/computation distribution is introduced and evaluated. We re-visit previous work of Li and Chen 13, 14], and we show that their alignment step should not be conducted without preserving the potential parallelism. In other words, the optimal alignment may well sequentialize computations, whatever the distribution after-wards. We provide an eecient algorithm that handles alignment and data/computation distribution simultaneously. The good news is that several important instances of the whole alignment/distribution problem have polynomial complexity, while alignment itself is NP-complete 13]. Mots-cl es: techniques de compilation, boucles parall eles, alignement, distribution, r egle du \the owner computes". Abstract In this paper, an eecient algorithm to simultaneously implement array alignment and data/computation distribution is introduced and evaluated. We re-visit previous work of Li and Chen 13, 14], and we show that their alignment step should not be conducted without preserving the potential parallelism. In other words, the optimal alignment may well sequen-tialize computations, whatever the distribution afterwards. We provide an eecient algorithm that handles alignment and data/computation distribution simultaneously. The good news is that several important instances of the whole alignment/distribution problem have polynomial complexity, while alignment itself is NP-complete 13].
منابع مشابه
Alignment and Distribution is NOT (Always) NP-Hard
In this paper, an efficient algorithm to simultaneously implement array alignment and data computation distribution is introduced and evaluated. We revisit previous work of J. Li and M. Chen (in ``Frontiers 90: The Third Symposium on the Frontiers of Massively Parallel Computation,'' pp. 424 433, College Park MD, Oct. 1990; and J. Parallel Distrib. Comput. 13 (1991), 213 221), and we show that ...
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