Performance of Collective Communications on Interconnection Networks with Fat nodes and Edges

The paper deals with scheduling collective communications in the minimum number of communication steps; it shows how to generalize the known results regarding time complexity of collective communications on common direct networks for the same networks with fat nodes and edges. Models of node architecture composed of several processor cores that share a router are discussed. Examples of communication algorithms on fat K-ring networks with 8 to 32 processors are summarized and given in detail. The results show that fat networks, depending on their configuration, can provide a range of communication performance at a lower cost.