Power Mac G5 is Apple’s best work yet

See correction at end of article

Companies large and small routinely set their expectations of computer systems according the capabilities of Intel-based x86 computers and 32-bit Windows. We’re due for a shift in standards.

Enter Apple, which got the bright idea of taking a pair of 64-bit IBM PowerPC CPUs, jacking them into server-class internal buses, and squeezing the whole thing into a desk-side tower chassis. The result, the Power Mac G5, delivers on the present need for rapid computing, deep multitasking, and responsive user interfaces — as well as the future need (current for some, including myself) for mainstream computers that rapidly process and analyze massive data sets.

If you’re on the edge of your seat waiting for a characterization of the Power Mac G5’s performance, here it is: Comparing official Standard Performance Evaluation Corporation (SPEC) dual-processor throughput tests with the unofficial numbers on Apple’s Web site, the 3.06GHz Xeon bests the 2GHz Power Mac G5 by some margin.

But wait, doesn’t Apple call the Power Mac G5 the world’s fastest PC? Yes, and I think that characterization was a big mistake from the beginning. The x86 architecture has the Intel compiler suite on its side. The Intel compilers are used to create most commercial and performance-sensitive applications for x86 software running on Windows and Linux. Apple won’t beat it until IBM gets serious about an architecture-tuned compiler for OS X.

Apple’s marketing choices aside, I believe that I/O throughput, especially memory performance, is infinitely more important than raw computing speed. Using the University of Virginia’s Stream memory bandwidth benchmark, the Power Mac G5 moves data almost twice as fast as a dual-processor 3.06GHz Xeon system: 2.2GB per second versus 1.3GB per second. (By way of comparison, memory throughput on a 17-inch PowerBook is 535MB per second.) I’m not cutting Apple special slack. Solid processing power and maximum bandwidth rule the day, and the Power Mac G5 has that combination down.

In a dual-processor Power Mac G5, the cost of talking to peripherals is also reduced substantially by the machine’s efficient and highly integrated system chip set. With the Power Mac G5, the penalty for accessing data that’s not in the CPU cache is reduced to a degree not possible with Xeon.

The Power Mac G5 takes the throughput flag, and it’s got something else you can’t get on the Xeon: the Panther OS (aka OS X 10.3). The client version firms Apple’s lead in graphics, boosting the performance of overall rendering and dramatically improving the display speed of PDF files. Panther server tightens links to Windows and Unix networks; reworks its directory services around open standards and a high-speed database; and adds a unified management interface that controls, among many other things, the new mail server, a Microsoft-compatible VPN, and streaming video services. As has long been true, the Mac is the platform to beat for client Java. Panther Server includes the open-source JBoss J2EE application server, complete with graphical administration and monitoring. The Panther client is beautiful and practical, while the server is powerful and painless.