DISTRIBUTED MEMORY

DISTRIBUTED MEMORY

·         Refers to multiple-processor computer system in which all processor has its own memory.

·         Computational task can only operate an local data

·         One or more remote processor must be communicated by computational tasks if remote data is required.

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·         Architecture of a distributed memory:

=a processor

=a memory

=some form of interconnection that allow programs in each processor to interact with each other…

·         Below is a diagram of architecture of distributed memory of 3 computers:

·         The interconnect can be organized with point-to-point links or separate hardware which can provide a switching network.

·         Network topology=key factor determining how the multi-processor machine scale.

·         Implementation of links between nodes:

=using some standard  network protocol (eg: Ethernet)

=bespoke network links (used in Transputer)

=dual ported memory

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·          In distributed memory ,there is also distributed shared memory in which each node of cluster has access to a large shared memory in addition each node’s limited private memory.

·         There are comparison between shared memory , distributed memory and distributed shared memory:

=(distributed) shared memory offer a unified address space in which all data can be found

=distributed memory can exclude race conditions and force the programmer to think about the data distribution.

=distributed (shared) memory easier to design a machine that scales with algorithms

=Distributed shared memory hides the mechanisms of communications (does not hide the latency of communication)…

Ku Man Yi
B031210161