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Is it a processor? A computer?

It seems that wherever I look, the term is very vaguely defined... perhaps it means many things in different contexts?

fixer1234
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Dark Templar
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2 Answers2

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the term is very vaguely defined

This is because in supercomputing – or parallel, grid computing, or even any other field in computer science), a "node" is anything that takes a job and processes it on its own, without needing another node to do it.

The definition is vague since anything can be a "node" depending on the context.

  • In a PlayStation 3 cluster, this would most likely mean the game console itself.
  • In a network simulation (i.e. self-organizing ad-hoc networks), it would be the "virtualized" node running in the simulation software.
  • In a heterogenous cluster (i.e. for Folding@home), it would be the client software running within any operating system of any computer – i.e. "node" doesn't really refer to any hardware or OS, but rather the processing software.
  • In supercomputing, as the supercomputer is composed of multiple smaller units, these are called nodes
  • et cetera
slhck
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In that context, it means an Operating System instance. An OS commonly but not always runs on top of more than one CPU but it isn't necessarily using a whole computer as you can have more than one OS running.

Nowadays, most if not all of the supercomputers are basically composed of a large number of computers interconnected by fast links. Each of these computers are named nodes, a term that has always been used in networking to identify an active device on a network.

Thus each of these single computers are called nodes, they can have an arbitrary number of CPUs, cores, threads, whatever but undoubtedly run a single OS instance.

I have never heard nodes to mean single CPUs on a multi-CPU server. Here is for example how Intel defines nodes: Node - Intel

jlliagre
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  • I've heard people at university referring to CPUs as nodes, that could be a translation issue as well. It is a very generic term. – slhck Sep 17 '11 at 22:24
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    It might be a generic term, but not in the context of supercomputing, which is what this question is about. Node meaning a CPU would have been a very non standard usage. – jlliagre Sep 18 '11 at 06:26