Parallelizing NP-Complete Problems Using Tree Shaped Computations
نویسنده
چکیده
We explain how the parallelization aspects of a large class of applications can be modeled as tree shaped computations. This model is particularly suited for NP-complete problems. One reason for this is that any computation on a nondeterministic machine can be emulated on a deterministic machine using a tree shaped computation. We then proceed to a particular example, the knapsack problem It turns out that a parallel depth rst branch-and-bound algorithm based on tree shaped computations yields superlinear average speed-up using 1024 processors. This even holds for large relatively easy problems which produce a very irregular search tree and only a moderate amount of work.
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