Optimal Task Assignment in Hypercube Networks

Sang-Young CHO  Cheol-Hoon LEE  Myunghwan KIM  

IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences   Vol.E75-A   No.4   pp.504-511
Publication Date: 1992/04/25
Online ISSN: 
Print ISSN: 0916-8508
Type of Manuscript: Special Section PAPER (Special Issue on Discrete Mathematics and Its Application)
combinatorial algorithm,  homogeneous network,  hypercube network,  maximum flow,  minimum cut,  network flow,  optimal algorithm,  task assignment,  

Full Text: PDF(679.5KB)>>
Buy this Article

This paper deals with the problem of assigning tasks to the processors of a multiprocessor system such that the sum of execution and communication costs is minimized. If the number of processors is two, this problem can be solved efficiently using the network flow approach pioneered by Stone. This problem is, however, known to be NP-complete in the general case, and thus intractable for systems with a large number of processors. In this paper, we propose a network flow approach for the task assignment problem in homogeneous hypercube networks, i.e., hypercube networks with functionally identical processors. The task assignment problem for an n-dimensional homogeneous hypercube network of N (=2n) processors and M tasks is first transformed into n two-terminal network flow problems, and then solved in time no worse than O(M3 log N) by applying the Goldberg-Tarjan's maximum flow algorithm on each two-terminal network flow problem.