Ultracomputer

The NYU Ultracomputer is a significant processor design in the history of parallel computing. The system has N processors, N memories and an N log N message-passing switch connecting them. The switch uses an innovative fetch-and-add instruction which will combine references from several processors into a single reference, to reduce memory contention.

The machine was developed in the 1980s at the Courant Institute of Mathematical Sciences Computer Science Department, based on a concept developed by Jacob T. Schwartz. Most of the work done was theoretical, but two prototypes were built:<

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