Submesh Allocation in Mesh Multicomputers Using Busy-List: A Best-Fit Approach with Complete Recognition Capability

Abstract

A new approach is proposed for dynamic submesh allocation in mesh-connected multicomputer system, which supports a multiuser environment. The proposed strategy effectively prunes the search space by searching for free submeshes on the corners of allocated (busy) submeshes along with the four corners of the mesh system. A submesh is selected with the potential of causing the least amount of fragmentation in the system. The proposed strategy possesses complete submesh recognition capability; it is a best-fit strategy, as well. Existing strategies do not provide this combination of capabilities. The deallocation time and memory overhead are shown to be constant in that they do not grow with the size of the mesh. To demonstrate effectiveness, the performance of the proposed strategy is compared against all existing schemes. Simulation results indicate that the proposed strategy outperforms existing ones in terms of parameters such as average delay in honoring a request, standard deviation of delay, average allocation time, average deallocation time, and amount of memory required. The proposed scheme achieves a 20 to 30% improvement in the average waiting delay over the best performing existing algorithm to date. Our scheme is shown to be applicable to torus-connected multicomputers as well, with only minor modifications. The scheme can also be used for submesh allocation with failures.