Introduction to Multiprocessors - Fundamentals of Computer Organization and Architecture - page 245

in applications such as image processing. Famous real-life machines that have been
commercially constructed include the ILLIAC-IV (1972), the STARAN (1974), and
the MPP (1982).
Two main SIMD configurations have been used in real-life machines. These are
shown in Figure 11.7.
In the first scheme, each processor has its own local memory. Processors can
communicate with each other through the interconnection network. If the intercon-
nection network does not provide direct connection between a given pair of pro-
cessors,

then this pair can exchange data via an intermediate processor. The

Figure 11.7 Two SIMD schemes. (a) SIMD scheme 1, (b) SIMD scheme 2