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Our two primary test programs were SETI@home and Let1kWindowsBloom. A good question to ask is: what are these?
SETI stands for “Search for Extra Terrestrial Intelligence.” In an effort to take this concept out of the hands of the tabloids and turn it into a valid scientific effort, The Planetary Society (http://planetary.org/) and the University of California Berkeley (http://www.berkeley.edu/) have combined resources to support the world’s most ambitious computer-based research project. After collecting radio telescope data from the massive Arecibo Observatory in Puerto Rico (http://www.naic.edu/), the SETI@home project slices up the raw data into digestible chunks and sends it out over the Internet to millions of computers worldwide.
These computers use the free SETI@home client to crunch the data down, looking for interesting patterns, and then upload the finished work back to the SETI@homedata center in Berkeley, California. The finished work is called a “work unit,” and the user’s client keeps track of how many work units have been completed, how long the computer has been working on the current unit, and how many computer hours a particular user has devoted to the project. Launched on May 13, 1999, by October 2003 the project had received over a billion work units from 4.7 million users around the world. To read about the project, and get a copy of the free client, see the SETI@home Web site at http://setiathome.ssl.berkeley.edu/.
While SETI@home has not been tweaked to take advantage of the Power Mac G5’ PC970 chip (the program has no clue it is running on a 64-bit processor, and probably doesn’t know what to make of the twin AltiVec processors built in to each PC970), it seemed like a good candidate for tests. First, it is free. Second, it is familiar, with millions of users on Wintel, Macintosh, Linux and UNIX computers. Third, it is a known CPU hog: if SETI@home is running, everything else grinds to a halt.
For Mac OS X, the program comes in a command-line version, good for techies, and a more common GUI version with a graphical user interface. We always run the GUI version as an application, not a screen saver, since the screen saver tends to be too greedy and prevents other applications from working.
SETI@home “work units” require varying amounts of processing power. A relatively “quiet” chunk of data may not require much work, while a chunk with lots of varying data may require twenty to fifty percent more time. Despite the variance, it is a great program for helping pick out the fast computers from the slow.
Let1kWindowsBloom has a different purpose entirely. The same program can run in either Mac OS 9 or Mac OS X. It has just one function: to open exactly 1,000 windows on a Mac as rapidly as possible, and then tell you how long it took to do this. The author, Rob Terrell, notes that it really isn’t much of a benchmarking program, and we noted in our test that the same machine can give slightly different results at different times, for reasons not entirely clear. But the results are generally the same. And, since opening and closing windows is a very common activity, it struck us as a good indication of the perceptual speed of a computer. Computer scientists might argue that determining computer speed calls for objective, quantifiable measurements, but in reality any computer user knows that the key factor is perceptual speed. A fast computer seems fast, a slow computer seems slow, and objective measurements aren’t really relevant.
Another key consideration for us: Let1kWindowsBloom is free: http://www.vgg.com/rob/WindowsBloom.html
Most magazine reviews have concentrated on benchmarks done with Adobe Photoshop 7.0. Typically, a magazine review will state something like: “We took a dual-processor Power Mac G5 with 4 GB of memory and used Photoshop 7.0 to manipulate a 120 MB CYMK image of a tufted puffin, applying a cubic hyperspheriodal filter to a truncated tessellated polytrophic ellipsoidal segment, extruding it through eye-of-the-needle Hessian FFT transforms into a RGB layered image (with sepia secondary sequences) of Catherine Zeta-Jones.” While this sounds fascinating, we have no idea what it means, much less how to do it. And unless you are a puffin or Michael Douglas, this isn’t something that “normal people” are likely to do during an average day.