What is a farm, as opposed to a grid or a cluster?

Question

I'm trying to understand does "farm" mean in computing, so that, if a farm can be exemplified as a cluster, there must be something that a farm is independently of what a cluster is.

How is it different than a grid?

Do these concepts have a general meaning, where talking about for example web servers is only one common scennario, or do they differ deppending on the context completely? If so, what are the different meanings (or the most common ones)?

Also, should I be asking this somewhere else? (If so, my apologies).

Hally

Answer 1

I'll have a go:

A server farm is a group of servers, which may or may not be clustered, that together offer a higher computing capacity for a particular goal than an individual server. An example is a Web farm, which typically consists of a number of load-balanced Web servers, each with the same content and configurations.

While a farm may be clustered, typically a cluster consists of servers that are configured in a failover scenario, for instance active/passive, meaning that, say, 1/2 the servers are on active duty while the rest becomes activated only when the servers on active duty are no longer accessible. So when a server in the cluster crashes, it is not a problem because another server takes over.

A grid then is typically a configuration of computers that work together (in parallel) to solve a complicated task, such as organic chemistry computations or playing chess against the world champion. The work is divided into parts and each computer takes on a part and reports its findings to the main node which then synthesizes the final result.

I hope this helps.

Some links:

Wikipedia definition of server farm: http://en.wikipedia.org/wiki/Server_farm

Wikipedia definition of computing cluster: http://en.wikipedia.org/wiki/Cluster_(computing)

Wikipedia definition of grid computing: http://en.wikipedia.org/wiki/Grid_computing

Calorific

Thanks, I actually decided to ask because those articles didn't help me answer what is a farm that is not a cluster or a grid, and how should I use the term. But I'll keep reading until familiarity solves it. – Hally

Does my answer not answer your question? – Calorific

It does, but partially... Is a farm always of servers? If not, is it only a group of computers? As in, if it is a grup of computers, is it localized or deloclized (for example)? or can one call it a farm in any case? etc. I am looking for what a farm means univoquely, if it is so, or for a declaration of it's synonimic / equivoque nature, or analgous, or whaterver it is. For example, if it is accidental to the notion of clusters, perfect, that could be, but I still don't know... Because I am a bit (or a ton) confused... – Hally

First of all, what purpose would a client farm serve? You might be creative and come up with scenarios but I'd say that, for all practical purposes, farms are composed of servers, yes. After all, that is why they are farmed together, to provide high server capacity. It also makes sense to view a farm as strictly local; you may have mirror farms in other locations but they would be farms in their own right. – Calorific

So if an imaginary company uses a render farm of it's own, we can still say without much discussion, as in, it is usually enough said that way, that such a render farm uses the client-server arch primarilly, where maybe the server is all the rendering units and the client is them wanting the frames rendered... or something like that? – Hally

I'm not familiar with render farms, I don't know if they fit in a client/server scenario or if that is just a name for a group of computers that each render different images. – Calorific