Lawrence Berkeley National Laboratory
Power Play
NERSC Makes High-Performance Computing Accessible
By Thomas R. O’Donnell
The personal computers in Lawrence Pratt’s laboratory weren’t cutting it. His research on the structures and interactions of lithium compounds was hindered because the Pentium 4-type machines he uses at Fisk University in Tennessee couldn’t keep up with the demands of modern computational chemistry.
His work finally kicked into high gear with a grant of 150,000 high-performance computer processor hours — and the help of the National Energy Research Scientific Computing (NERSC) Center, based at the Department of Energy’s Lawrence Berkeley National Laboratory (LBNL) in California.
“I use every last minute” of computer time, says Pratt, who got onto the powerful NERSC machines through the DOE’s Innovative and Novel Computational Impact on Theory and Experiment (INCITE) program. He’s since qualified for another grant of 150,000 processor hours and “I’m burning through it like crazy, but I’m also publishing a lot of papers — five so far this year.”
As INCITE projects go, Pratt’s is small. Most INCITE projects, which hold potential for major scientific breakthroughs, are awarded millions of processor hours — but they consume up to 20 percent of the hours available on NERSC’s massively parallel computers, says center director Horst Simon. The remaining 80 percent is divided among 300 or so projects, each using tens of thousands to millions of processor hours per year. A small amount of time is set aside for “startups,” or researchers who are still preparing their software for massively parallel processing.
Simon would be happy to have more such projects use NERSC computers as a gateway to high-performance computing. In particular, he’s working to provide more students — especially DOE Computational Science Graduate Fellowship (DOE CSGF) participants — more opportunities to try their programs. “We want to get students interested in using NERSC or any of the other DOE computational resources, so they have a positive experience and become used to integrating scientific computing into their work,” especially after graduation, says Simon, who is leaving his post soon to concentrate on other roles at the Berkeley lab.
The center is a perfect place for a first taste of science on massively parallel computers. For more than 30 years, it’s been DOE’s main production center for scientific computing, and it hosts some of the department’s largest, fastest systems for unclassified research. More than 2,500 users from dozens of universities, private research institutions and DOE laboratories work on around 300 projects each year. Yet, users rarely visit the NERSC facility. Most connect to and use center computers via ESnet, DOE’s high-speed network, and the Internet. Their work produces mountains of results — for 2006, researchers published more than 1,400 papers related to calculations on NERSC computers.
The NERSC Center’s role as a DOE service facility means the projects running on its computers cover virtually every strategic theme pursued by DOE and its Office of Science — “Everything from astrophysics down to nanoscience,” Simon says. Fusion energy, materials science, chemistry, climate, genomics, computational biology, applied math and computer science are just some of the disciplines with research on NERSC Center machines. “Our mission is really to be the high-end production resource for the Office of Science, so general purpose and diverse applications have been part of our mission,” Simon adds.
In-house expertise is part of what makes the NERSC Center popular with researchers. The staff works with computational scientists to tune applications for the best performance, visualize their results and make their research more effective. There’s a strong culture focused on assisting users, and the staff is experienced and stable, Simon says. The center stages regular training sessions, encourages user communities to exchange information, and hosts databases of user questions.
