A Performance Comparison of Contiguous Allocation Placement Schemes for 2D Mesh-connected Multicomputers

Several contiguous processor allocation policies for two-dimensional mesh-connected multicomputers have been proposed over the past fifteen years. These policies typically consist of a detection phase and a placement phase. The detection phase finds submeshes that can accommodate the current allocation request, and the placement phase chooses a free submesh where allocation will take place and a position for the allocated submesh within this submesh. The performance of allocation policies depends on their ability to detect free submeshes, and on the placement policy used. Several placement schemes have been considered in previous research works, but no realistic performance comparison between them is available. In previous comparisons, the placement and detection schemes were lumped together. This paper presents the results of detailed simulations that were carried out to evaluate and compare several placement schemes that cover a wide range of choices. In these simulations, a single complete-recognition free submesh detection algorithm is used with all placement schemes considered.