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Shared Memory Computers

A shared memory computer, sometimes referred to as Symmetrical Multi-Processor (SMP) architecture, consists of multiple processors sharing the same memory. Since the capacity of the communication bus is shared between all the processors, the memory access time increases with the number of processors. To do this process more effective, each processor has fast cache memory (very expensive, mostly more then processor itself) which, if properly used, significantly reduces the communication time. Nowadays, the most attractive SMP are two ways PIII processors from Intel. The increase of price with number of shared processor is highly nonlinear and from the point of computational mechanics non-effective (this can be demonstrated on two clusters at Cornell - cluster with 2ways PIII processors is faster than cluster built on 4ways PIII Xeon processors, which are significantly more expensive).

Next: Distributed Memory Computers Up: Parallel Computers Previous: Parallel Computers

Daniel Rypl
2005-12-03