- 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. Also, processing in this manner. This contrasts with massively parallel processing, 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. This also contrasts with asymmetric multiprocessing, in which multiple CPUs are each assigned a specific task, with all CPUs controlled by a master processor. Also spelled symmetrical multiprocessing. Its abbreviation is SMP. Also called tightly-coupled multiprocessing.