According to the press release, the XT4 designed to easily and efficiently scale to a peak performance of more than one petaflops (1,000 trillion floating-point operations per second). Evolved from the Cray XT3 supercomputer, the Cray XT infrastructure provides a common, scalable environment for login, compilation, resource management, work scheduling and I/O. This environment also includes a unique globally shared, high-performance parallel file system, as well as network interfaces to other systems.

"While the theoretical peak speed of supercomputers may be good for bragging rights, it is not an accurate indicator of how the machine will perform when running actual research codes -- which is what our 2,500 users are most interested in," said Horst Simon, director of the NERSC Division at Berkeley Lab. "To better gauge how well a system will meet the needs of our users, we developed SSP, a sustained system performance benchmark suite. Under this real-world performance test, the new Cray XT4 system will deliver over 16 teraflops on a sustained basis."

The Cray XT4 supercomputer uses up to 30,000 AMD Opteron dual-core processors interfaced to the Cray SeaStar2 interconnect chip. Unlike typical cluster architectures, in which many microprocessors share one communications interface, each AMD Opteron processor in the Cray XT4 system is coupled with its own interconnect chip. Providing six links in three dimensions, the SeaStar2 chip uses its embedded routing capability to take advantage of HyperTransport technology and accelerate communications among the processors

"Unlike commodity clusters, the Cray XT4 supercomputer is built from the ground up to provide a scalable, balanced system in order to support the most demanding applications," said Cray President and CEO Peter Ungaro. "The Cray XT4 system builds upon our highly successful Cray XT3 supercomputer in almost every aspect, providing enhanced scalability, performance and reliability in a system that is easily upgradeable to protect a customer's investment for years to come."

Cray XT4 supercomputers configured with dual-core Opterons are available now. Furthermore, Cray says that current XT4 systems will be upgradable to AMD's quad-core processing technology when available.