Shared Memory Model
The processors are all connected to a "globally available" memory, via either a software or hardware means. The operating system usually maintains its memory coherence.
From a programmer's point-of-view, this memory model is better understood than the distributed memory model. Another advantage is that memory coherence is managed by the operating system and not the written program. Two known disadvantages are: scalability beyond thirty-two processors is difficult, and the shared memory model is less flexible than the distributed memory model.
There are many examples of shared memory (multiprocessors): UMA (Uniform Memory Access), COMA (Cache Only Memory Access) and NUMA (Non-Uniform Memory Access).
Read more about this topic: MIMD
Famous quotes containing the words shared, memory and/or model:
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