iCluster - Build an imac Cluster

What better thing could you do with 4 imacs than turn them into a cluster?

A cluster, for anyone wondering, in general terms, is a group of connected computers that work together to complete a task. 

Step 1: Materials

The list is surprisingly short and contains extremely common parts.

4 Apple computers. I used G5 Intel imacs but you can use any Apple computer.
4 Category 5 Ethernet cables
1 10/100Mbps Ethernet switch (minimum 4 ports)
1 key board and mouse
1 USB

In my case, I got all of the imac because they had broken/missing screens. All you need then is a monitor, VGA cable, and VGA adapter depending on the type of port on your Apple.

Comments

[CVBruce]

Each of your iMacs should have a 10/100/1000 ethernet port, so using a 10/100 hub is slowing down communication between them. It depends on the workload, but this could impact the speed of the cluster.

I've used Xgrid, and it was pretty cool to see my workload spread over multiple machines, even different architectures, powerpc and intel. I was using software to encode video files.

Another possibility is, if just the screens are bad, then you can still use the GPUs for processing.

[Hammock Boy]

It probably did slow down the speed of the cluster, but I used the 10/100 hub because it was what I had, and since I never had a long term use for it, it did not matter.

I have not used Xgrid before, but I would imagine that it is faster and more versatile than Pooch.

[CVBruce]

Here is some good info on Xgrid. I don't know that Apple is actively supporting or developing it any more.

http://www.macresearch.org/the_xgrid_tutorials

[RogueOne]

You should check out Xgrid, which is part of the Server version of OS X now. It allows you to "easily" spread processor intensive tasks across multiple Macs.

[Hammock Boy]

Have you worked with it before? It would be neat to get an actual cluster going with 8-10 imacs.

[Hammock Boy]

If anyone has any ideas on how to improve this I would love to hear them.

[provocativetimbre]

Sorry, but doesn't it seem a bit silly to use imacs to get something like this done? wouldn't it be better just to use a few towers, just because all the imacs are self contained and a tad unruly.

[Hammock Boy]

I wouldn't mind having a few towers but I only had the iMacs at my disposal. I'm a little confused as to what is wrong with the iMacs bieng self contained since I did have to physically change anything about them. Please explain.

[rch]

Very interesting. I tried to experiment around with a cluster using Linux powered PC's many years ago with something called Beowulf.

Any idea on how long the version of Pooch will run before it expires?

Nice job scoring 4 iMacs, even without monitors, a very nice platform for experimenting with. Where did tou get them, and for how much?

[Hammock Boy]

I believe that Pooch runs for 10 days and then it expires, although, you can immediately download a new copy. I'm not sure then why there even is an expiration date?

The imacs were all free - from a dumpster - my school threw them out because of the bad screens and it was deemed cost effective to just buy new computers. That is also where I got the Ethernet cables. It turned out that the only thing that I had to buy for this project was the network switch. Everything else I already had.

Did you get the Beowulf to work?