The DADO production system machine
Salvatore J. Stolfo, Daniel P. Miranker · Journal of Parallel and Distributed Computing · 1986
DADO is a parallel, tree-structured machine designed to provide significant performance improvements in the execution of large expert systems implemented in production system form. A full-scale version of the DADO machine would comprise a large set of processing elements (PEs) (on the order of thousands), each containing its own processor, a small amount (20K bytes, in the current prototype design) of local random access memory, and a specialized I/O switch. The PEs are interconnected to form a complete binary tree. This paper describes the application domain of the DADO machine and the rationale for its design. Parallel algorithms for production system execution are briefly described. We then focus on the machine architecture and detail the hardware design of a moderately large prototype comprising 1023 microprocessors currently operational at Columbia University. We conclude with very encouraging performance statistics recently calculated from an analysis of simulations of the system.