Implementation of divide-and-conquer algorithms on multiprocessors
Algorithms with a divide-and-conquer structure are suitable candidates for parallelization. The idea of the divide-and-conquer paradigm is to fragment a problem into subproblems of the same kind, to solve the subproblems recursively, and, finally, to combine the solutions of the subproblems into a solution of the original problem.
Two algorithms of this structure namely an “approximation” algorithm for the Euclidean Traveling Salesman Problem and an algorithm to determine the convex hull of a two-dimensional point set have been implemented in FORTRAN on a CRAY X-MP using the CRAY multitasking facilities. For the parallel implementation of algorithms with a divide-and-conquer structure two methods are discussed. The goal was to find an implementation strategy which is independent of the available shared memory multiprocessor system and additionally independent of the number of processors which can be used to find the problem's solution.
KeywordsMultitasking macrotasking microtasking CRAY X-MP divide-and-conquer parallel algorithm Euclidean Traveling Salesman Problem convex hull
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