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

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 for parallel processing in MacOS 8.1 and higher, one must set the AppleTalk Control Panel to use the appropriate Fast Ethernet Adapter and verify in the chooser that AppleTalk is active. Next, a unique computer name must be set and Program Linking should be enabled in the File Sharing Control Panel. Finally, in the Users and Groups Control Panel, one must allow Guests to link. (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 MacOS 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 three additional items from our web site: the Launch Den Mother utility, the AutoGuest Control Panel, and the Parallel Fractal Demo. Copy the AppleSeed folder containing the Launch Den Mother to the top directory of each Mac in the cluster, and drag and drop the AutoGuest Control Panel to the System Folder. Restarting each computer completes the software installation. Congratulations! You've just constructed your own parallel computer.

Testing the Cluster

To test it, we recommend you first run the Parallel Fractal 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 Parallel Fractal Demo program to the Launch Den Mother, select the computers you want to run it on, and click on "Launch Executables". 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].