MULTIPROCESSING(frist)
An expanded metal organizational technique in which a number of processor units are employed in a single computer system to increase the performance of the systerm in its application environment above the performance of a single processor. In order to cooperate on a single application or class of applications, razor wire the processors share a common resource. Usually this resource is primary memory, and the multiprocessor is called a primary memory multiprocessor. A system in which each processor has a private main memory and shares secondary memory with the others is a secondary memory multiprocessor, sometimes called a multicomputer system because of the looser coupling between processors. The more common multiprocessor systems incorpotate only processors of the same type and performance and thus are called homogeneous multiprocessors, architectural mesh however, heterogeneous multiprocessors are also employed. A special case is the attached processor, in which a second processor module is attached to a first processor in a closely coupled fashion so that the first can perform input/output and operating system functions, enabling the attached processor to concentrate on the application workload.