Practical Array Architectures

In each category of computer architecture, be it parallel or sequential, there are often one or two machines which embody a large majority of the principal techniques for that category of machine. In this text we have chosen to use the ICL Distributed Array Processor (DAP) and the TMC Connection Machine as examples of SIMD processor arrays, as they have particular significance, by virtue of their position in the chronology and taxonomy of these types of machine. The DAP, for example, was the first commercial exploitation of this style of architecture, a style which can be traced back many years. In particular, the design of the DAP owes much to the pioneering work carried out on the SOLOMON computer [SBM62], and later on the ILLIAC IV computer [BBK*68]. The Connection Machine represents a more recent evolutionary step embodying the integration of several processing elements on a single chip, and the consequent production of a massively parallel system. The target applications, and programming language, of the Connection Machine are also a departure from the conventional view of array processors as providers of high performance numerical facilities, and this is explored in more detail in the following chapter.