Sun Microsystems has shed more light on its UltraSPARC roadmap, outlining plans for two new processor families that will use multi-threading techniques to boost the performance of its servers.

The chip families, dubbed Niagara and Rock, will both cram several processor cores on a single piece of silicon, allowing them to execute potentially dozens of threads simultaneously, according to Sun.

Multi-core processors
Niagara and Rock will be Sun's second and third generations of multi-core processors, respectively. The first generation includes the UltraSPARC IV, which puts two UltraSPARC III cores on one piece of silicon. Sun announced this week that the chip will be available in servers next month, and said it offers about twice the performance of the UltraSparc III.

"UltraSparc IV represents the first generation of chip multi-threading technology. It covers the sweet spot of today's requirements," said David Yen, executive VP of Sun's processor and network products group. "Our second-generation multi-threaded chip, Niagara, is network-facing and focussed on handling tomorrow's throughput requirements. Beyond Niagara we will introduce the third generation of chip multi-threading - the data-facing Rock family. The intent there is to try to get the best of both worlds."

Niagara, which Sun has discussed briefly before, will be geared towards network-intensive applications, Yen said. UK marketing manager John Tutcher said Sun expects to use Niagara in its blade servers, where it could eventually boost performance by as much as 15 to 30 times compared with Sun's UltraSPARC III, though performance benefits from the recently launched CPUs will be closer to 1.5 to 1.95 times the performance.

The Niagara family will address the problem by dedicating some of its threads to processing network packets, he said. Solaris 10, an upgrade to Sun's operating system due at the end of 2004, will have the ability to recognise different packet types and direct them to the appropriate thread for processing, he said.

Yen added, "We are not getting into the network processor business. It's a general-purpose, multi-threaded processor. We are simply taking advantage of the existence of multiple hardware threads to sort out the requirements of different types of tasks. We can even dedicate extra silicon to do some computing jobs like cryptography."

Chips in the Rock family, which will come after Niagara, will use their multi-threading capabilities to handle a variety of tasks more quickly including computation - for running a databases and ERP systems, for example - and other types of work such as encryption, Yen said.

Tutcher added that future systems will major on massive parallelism, with up to eight execution units per CPU, each with four threading units - a total of 32 threads. Sun didn't offer a timetable for delivering the chips, but the Niagara family is due some time in 2005 or 2006
According to Tutcher, benefits include lower heat dissipation and savings in floor space, administrative and environmental costs through CPU consolidation.

Beyond UltraSPARC IV
On Tuesday, Scott McNealy, Sun's chairman, president and chief executive officer, held aloft on stage the follow-on to the UltraSPARC IV, which goes by the code name Panther, or UltraSPARC IV-Plus. Yen said Wednesday that Sun has quadrupled the size of the chip's Level 2 memory cache to increase performance.

Sun's UltraSPARC competes primarily with IBM's Power4 processor and Intel's Itanium and Xeon chips. Sun said the forthcoming processors will provide evidence that its research and development spending is paying off. It will also be hoping that they help boost its revenues, which were flat last year after two years of decline.