IBM will next month ship the first four Unix servers to be based on its next-generation Power5 microprocessor, the company announced.

The servers will range in size from dual-processor to 16-way systems. They will begin shipping from August 27, IBM said. Apple's current Power Mac G5 processor is based on IBM's Power4 microprocessor.

The p5 server line includes the dual-processor p5-520, the 4-way p5-550, and the p5-570, which will support as many as 16 processors. A slimmed-down version of the p5-570, called the p5-570 Express, supports as many as eight processors.

The lower-end p5-520 and p5-550 servers will be available in both tower and 4U (17.8 cm) rack-mount configurations. IBM plans to announce smaller 1U (4.4 cm) and 2U (8.9 cm) p5 systems by September, company executives said. A larger server that will scale to as many as 64 processors will follow later in the year, they said.

Design goal
A major design goal for the p5 systems was to integrate mainframe-like technologies that would make them not only faster, but more efficient than other Unix systems in the way they use system resources, said Sanchez.

"The new p5 eServer product line is really about changing the game," he said. "It's about having Unix mature as a platform."

The p5s use a multithreaded and multicore chip design, which means that each of the Power5's two processor cores can run two tasks at the same time, making the Power 5 appear to the computer's operating system as though it has four processors.

The 276 million-transistor chips also use IBM's Virtualization Engine technology to divide each processor core into as many as ten virtual servers, a feature not available on Power4-based systems: "We put a hypervisor between the processor and the operating system that allows you to do virtualization," said Sanchez, referring to microcode that IBM has been using in its mainframe systems for years.

IBM hopes that customers such as Steve Kellogg, director of advanced information technologies at The Pennsylvania State University, will be able to use Virtualization Engine to be more efficient in the way they use their Unix systems. Kellogg's group has about 200 servers that run a wide variety of compute services for the University, including Web services, authentication, and a number of specialized applications.

Penn State has only begun its evaluation of beta versions of the p5-520 servers, but the idea of consolidating a larger number of operating system images on a single system is appealing, Kellog said. "I anticipate that we will be able to leverage more of the hardware resources that we have because of this capability," he said. "We over-provision, and this provides the level of virtualization that will help us not over-provision."

While IBM has also produced a number of benchmark results purporting to show the p5 systems' performance advantage over systems from HP and Sun Microsystems Inc., the mainframe-like characteristics that IBM has built into the systems are really what sets them apart, said Jonathan Eunice, an industry analyst with Illuminata Inc.

"I don't see Power5 as a performance play," he said. "IBM has been very modest in some of the performance things, but virtualization and fault management is where most of the important work has occurred."