Sun Breaks GHz Barrier
By Steven Fyffe -- EDN, November 26, 2001
Sun Microsystems Inc. last week formally said it has broken the 1GHz barrier with its Ultra SPARC III processor.
Texas Instruments Inc., which has used Sun products to break in new process technology for more than a decade, produced its first 1GHz capable Ultra SPARC chip about three months ago, said Peter Rickert, process technology development director at TI. But Sun waited to make the announcement until TI could guarantee delivery of large volumes. The Ultra SPARC III will be used first in desktop workstations then migrated up to midframe servers, Thomas said.
Jeff Thomas, Sun's VP of engineering, downplayed the megahertz milestone. "We are not having to play the consumer market like Intel, where you only have one metric to talk about, which is frequency," Thomas said. The chip performed well in benchmark tests that measure other aspects of performance.
The latest incarnation of the chip improved its integer benchmark by 32 percent, its floating-point performance by 72 percent and its overall clock speed by 17 percent, according to figures from the Standard Performance Evaluation Corp. (SPEC). TI's Rickert said the 100-nanometer transistors and faster copper process technology made a big difference to the Ultra SPARC III's overall speed. "A 17 percent increase in clock speed— that's clearly, primarily, a process improvement," Rickert said.
Analyst Nathan Brookwood said the most significant performance gains were due to Sun's improved compiler. "That's a good news-bad news situation. If you recompile all your programs, you will get a big boost in performance. The bad news is that most of the people that provide application software do not recompile too often. If you take an application that was already running on a previous generation of Ultra SPARC and you move it to the Ultra SPARC III at 1.05GHz, you really aren't likely to see the kind of improvement in performance that these compiler-sensitive benchmarks are showing."
While the beefed-up Ultra SPARC keeps Sun competitive, it is still not as fast as the POWER4 processor IBM released recently or as cheap as future generations of Intel Corp.'s Itanium processor promise to be, Brookwood argued. "Sun had been lagging some of its key competitors," he said. "With the 1.05GHz Ultra SPARC III, they are now in the ballpark, although they certainly haven't established any leadership positions here. "Ultimately, Sun's strategic dilemma is that IBM is serving the high-end above them, and they have the (Intel's) Itanium systems which are going to provide competitive levels of performance at probably substantially lower price-points than Sun can provide. You don't like to be stuck in the middle like that."
Sun's Thomas said the high benchmark results for IBM's POWER4 chip were misleading. Sun even included this skeptical analysis of IBM's results with the statement publicizing its own Ultra SPARC III numbers.
"Critics have pointed out that the scores claimed by IBM are achieved by executing test code with only one POWER4 core on an eight-core module, accessing cache memory that would otherwise be used by all eight cores on the module. Idling the other seven cores to achieve the fastest possible laboratory benchmarks is clearly an unrealistic operating condition that would not occur in the real world and generates results that do not scale beyond the one processor executing code on the module."
Thomas said the added performance of the IBM part came at the cost of die size and power consumption. "You get about 1.3 times better SPEC numbers, but the cost is roughly 10 times the area of our part. At best case we think it uses one-and-a-half times the power. It's a pretty expensive way to get that 30 percent improvement in the numbers."
