LIVERMORE, Calif. Lawrence Livermore National Lab is putting together a supercomputer that will boast nearly the same performance as the ASCII White system from IBM Corp. that the lab now uses but it promises to be 10 times cheaper. Called Evolocity, the system will be the fastest clustered supercomputer in the world, according to Lawrence Livermore.
At around 11 teraflops, the system will not be as fast as the IBM machine, which ranks as one of the world's fastest computers. But it will be far easier on the pocketbook, thanks to the use of off-the-shelf components and the open-source Linux operating system.
The system has a few unique features that the lab says will facilitate applications performance, including a fast, custom-made network that taps into an enterprisewide file system. "We have been using the File Transfer Protocol over Gigabit Ethernet, but now we will be able to read files directly from any available disk," said Mark Seager, assistant department head for terascale systems at the lab.
"This network approach is nice because we can use a standard PCI slot on each processor node, which gives a 4.5-microsecond latency," he said, as opposed to 90-µs latency for Gigabit Ethernet.
The network uses bus host adapters on each node, supporting a 320-Mbyte transfer speed in one direction and 400-Mbyte bidirectional throughput. Each processing node is a server board from SuperMicro Inc. (San Jose, Calif.), built around the Intel E7500 chip set with two Xeon processors running at 2.4 GHz. The boards are linked by a network assembled by Linux Networx into a clustered system that will have 960 server nodes.
The file system, called Lustre, uses a client/server model. Large, fast RAM-based memory systems support a metadata center, and data is represented across the enterprise in the form of object-storage targets. "Being able to share data across the enterprise is an exciting new capability. It will allow more collaboration among research projects," Seager said. For example, workstations on the network running visualization programs can directly access data generated by Evolocity.
"The 1- to 10-teraflops processing range is opening up a revolutionary capability for scientific applications. It's qualitatively different from what we have been able to do before," said Seager. The difference lies in the number of variables the computer can process at the same time and in the resolution of the simulation. Not only are simulations much closer to realistic physical experiments, he said, but it takes far less time to converge to a reasonable approximation.
"This type of capability elevates computer simulation to the same level as physical experiment and theory, so it is going to allow us to do groundbreaking scientific work," he said. Also possible will be realistic simulation of three-dimensional systems evolving over time, or many variable solutions of quantum mechanics wave equations. The lab plans to use Evolocity first in simulating the time evolution of molecules, studying the aging process in materials and doing first-principle computations from the Schroedinger wave equation.
Clustered supercomputers using off-the-shelf components have been pursued by smaller research groups. Evolocity shows that major labs can also reap benefits from the approach.