Getting the most out of SETI@Home on your Mac

These are just a few suggestions on how to use your idle CPU time most efficiently when running SETI@Home. I also have a few benchmarks and goals you can use to compare your own performance.

• Turn off Virtual Memory. Using VM means some apps requesting RAM allocation will get a chunk of hard disk space, which has much slower access times than physical memory. Since SETI@Home stores most of it's data in memory, using physical RAM is much faster than using virtual memory, which requires access through the SCSI or IDE controller, slowing down data access.
  
• Quit all other apps. This is pretty obvious. The less apps are open, the less CPU time and RAM being used, the more is available to Seti. If you really want to go hardcore, use NoFinder to quit the Finder as well.
  
• Use only screensaver mode, and blank the screen after 1 minute. Running Seti in windowed mode is highly inefficient, as it displays the graphic analysis all the time. For optimum performance in screensaver mode, select Preferences from the SETI@home menu, and tell it to blank the screen after 1 minute. Processing will be much faster without the graphic analysis display.
  
• Use the RAM disk trick. Open the Memory control panel, and allocate a RAM disk. What this does, is reverse a portion of your RAM to use a typical garden variety storage volume. Only being that it's physical RAM, it's very fast access. I recommend a 1MB RAM disk for your SETI files. Once you allocate it and reboot, open the System Folder, and go into the Application Support folder. Move the "SETI@Home data" folder there onto the RAM disk, then make an alias of the folder now on the RAM disk, and move that alias into the old location of the data folder. Now, when SETI goes to access the data files, it will inadvertently access them from the RAM disk, thus augmenting access times, and increasing the overall performance of your machine.
  

Some SETI@home benchmarks:

• UMAX SuperMac S900, 604e/200, OS 8.6, 64MB RAM: 34 hours, 20 minutes
• Apple iMac G3/400, OS 9.0.4, 192MB RAM: 12 hours, 30 minutes
• Apple PowerMac G4/450, OS 9.0.4, 128MB RAM, 8 hours 10 minutes
• Apple Workground Server 6150, 601/66, OS 8.6, 96MB RAM, 51 hours
• Apple PowerMac G4/500, OS 9.0.4, 384MB RAM, 5 hours 30 minutes
• Motorola StarMax, 603ev/160, OS 8.0, 64MB RAM, 42 hours 45 minutes

Hope all you Mac users out there find this helpful.

If you're in a real hurry to find extraterrestrials (or show off the power of your G3/G4), I've heard that running the SETI@home client through Mac OS X's terminal gives the speediest result you can hope to get on a Mac.

I like using the pretty display and password to keep certain people away from my computer when I'm out of the room, so I have no personal experience with this technique.