- A multiprocessing computer architecture in which multiple CPUs, usually in the same cabinet, share the same memory, and the same copy of the operating system, application, and data being worked on, during the execution of a single program or task. As more CPUs are desired or needed, they can be added. This contrasts with massively parallel multiprocessing, where each CPU has its own copy of the operating system, its own memory, its own copy of the application being run, and its own share of the data. Also, processing in this manner. Also called symmetric multiprocessing.