“The Penta-S: A Scalable Crossbar Network for Distributed Shared Memory Multiprocessor Systems”

It is well known that crossbar switch has the best performance among the multiprocessor interconnection networks. However expanding this switch so that the performance grows linearly with the number of processing elements (N) is costly and complicated. The size of the switch grows as a function of N. This paper presents an expansion scheme, which keeps the linearity between the performance, the number of processing elements and the number of switches.16x16 and 32x32 crossbar switch modules are used as building blocks of this scheme. It is a modular scheme as well and so nothing needs to be redesigned. The results of mathematical analysis show that the performance of this scheme is better than that of a Delta MIN built if 4x4crossbar switch modules (Delta-4) and comparable to that of MINs built with the same crossbar switch module size, i.e., Delta-16 and Delta-32.The cost efficiency of this scheme is better than that of any other network except Delta-4 MIN.