Recipe Icon AppleSeed:Recipe for Building a Simple Cluster
For Mac OS 9 and later  (Click for Mac OS 8.6 and earlier)

Step 1: Hardware

The easiest way to build a Macintosh cluster is to first obtain a number of Power Macintosh G3 or G4 computers. All the current models have built-in Fast Ethernet adapters. Next, obtain a Fast Ethernet Switch containing at least one port for each Macintosh and a corresponding number of Category 5 Ethernet cables with RJ-45 jacks. For each Mac, plug one end of a cable to the Ethernet jack on the Mac and the other end to a port on the switch. Turn everything on. As far as hardware is concerned, that's all there is.

Step 2: Configuration

To set up the Macintosh running Mac OS 9 and CarbonLib 1.2 or higher for parallel processing, make sure it is connected properly to the Internet as specified by your ISP. (If the Mac is on an isolated network, you can manually configure the TCP/IP control panel to use a unique IP address from to Finally, a unique computer name must be set in the File Sharing Control Panel. (Recommended: In the Energy Saver Control Panel, set the sleep time to Never (although it is okay to let the monitor go to sleep). This prevents the Mac OS from going to sleep while running a Fortran or C program.)

Step 3: Software

To run a parallel program on the cluster, you should download two additional items: Pooch, and the AltiVec Fractal Carbon demo. Double-click the Pooch Installer and select a drive for installation. Congratulations! You've just constructed your own parallel computer.

Testing the Cluster

To test it, we recommend you first run the AltiVec Fractal Carbon demo on a single node by double-clicking. Make a note of the execution time and speed. Then run it in parallel by dragging and dropping the AltiVec Fractal Carbon demo program to the Pooch Application, click Select Nodes..., select the computers you want to run it on, and, in the Job Window, click on Launch Job. By running the code in parallel, you should observe a noticeable speedup. To isolate bad hardware (e.g., a bad cable), we recommend starting two at a time and working your way up.

To write your own parallel software or for complete technical details, see our AppleSeed Development Page.

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Note: To build a Beowulf, a Linux-based cluster, we think the following 230-page book is an excellent introduction: T. L. Sterling, J. Salmon, D. J. Becker, and D. F. Savarese,How to Build a Beowulf, [MIT Press, Cambridge, MA, USA, 1999].