NUMA is short for Non-Uniform Memory Access. A computer with a NUMA memory design can configure a microprocessor cluster in a multiprocessor system, thereby increasing its performance and expanding system capabilities.

With NUMA, a processor can access its local memory faster than non-local memory.

NUMA is used in Symmetric Multiprocessing (SMP) systems. An SMP system is a system in which multiple processors running under a single operating system access each other's memory over a common bus or "interconnect" path.

The disadvantage of SMP is that when a microprocessor is added to the system, the shared bus or bus overload creates a performance bottleneck. NUMA adds some levels of buffering shared between microprocessors so that not all data access needs to be done on the main bus.