June 2007 Staff Research Notes

New Money, New Algorithms
Xiaoye “Sherry” Li has been awarded $10,000 from the France-Berkeley Fund, which aims to stimulate research exchanges among scientists from the University of California and France. Li, who is a researcher in CRD’s Scientific Computing Group, and her project co-leader from France, plan to use the money to further their work on developing novel algorithms for solving large sparse linear systems, used in many time-consuming computations in fields such as fluid dynamics, structural analysis and nanomaterial designs.

Both the Berkeley and the French teams include members who have developed some of the most widely used sparse solvers in the last decade. Li’s parallel SuperLU solver, for example, was the second-most downloaded code from the Berkeley Lab site in fiscal 2006. The solver has been a key in carrying out simulations for the design of International Linear Accelerator, the study of magnetohydrodynamics in fusion energy and the understanding of quantum scattering theory.

Current solvers are capable of tackling large sparse linear systems with more than one million equations. But the growing demand for high-resolution simulations will require new algorithms to solve systems with hundreds of millions of equations.

Iain Duff, project leader of Parallel Algorithms Group at CERFACS in Toulouse, is heading the French team. The 1-year project is scheduled to begin in January next year.

Defining Future Research
The third and final town hall meeting to brainstorm for novel computational science challenges ended at Argonne National Laboratory recently, with CRD scientists playing key roles in moderating discussions and reporting their findings.

The three town hall meetings, held first at Berkeley Lab and then at Oak Ridge National Laboratory last month, are part of an effort by ASCR to generate ideas for an innovative program for tackling new computational sciences and expand ASCR’s contributions to the DOE Office of Science mission over the next decade. The program is currently called Exsacle for Energy and Environment (E3).

During the first meeting at Berkeley Lab, scientists broke into nine groups to discuss subjects such as renewable energy, distributed computing, astrophysics and biology. Ideas from those discussions were further refined in the two subsequent meetings. Many researchers attended all three meetings.

More than a dozen CRD researchers are involved in drafting the final reports.    When the town hall meeting took place at Berkeley Lab, Lab Director Steve Chu presented a lunch talk about LBNL's increasing emphasis on energy efficiency and new, renewable energy sources. Chu underscored his case for increased investment by citing both economic and environmental factors, which show that current energy practices are too costly to sustain on a global scale.

SciDAC Show and Tell
CRD and NERSC scientists spoke and presented posters this month at SciDAC 2007, the conference that brought together recipients of the Scientific Discovery through Advanced Computing Program from DOE’s Office of Science. The program funds and brings together computational scientists, applied mathematicians and computer scientists from U.S. universities and national labs to work on algorithms and software development.

Phil Colella, John Shalf and Horst Simon were featured speakers during the five-day conference in Boston. Colella, head of the Applied Numerical Algorithms Group in CRD, talked about “Performance and Scaling of Locally Structured Grid Methods for Partial Differential Equations.”  Shalf, the head of the Science-Driven System Architecture Team at NERSC, presented “The New Landscape of Parallel Computing Architecture.” Simon, head of CRD and NERSC, presented a review of the three town-hall meetings on develop Exsacle for Energy and Environment (E3), a program for tackling novel computational sciences in the next decade.

Several CRD scientists also presented posters. They are John Bell, Andrew Canning, Lin-Wang Wang, Xiaoye Sherry Li, Parry Husbands, Brian Tierney and Arie Shoshani.

The conference took place in Boston this year. Berkeley Lab will host SciDAC 2008 in Seattlee. More information about this year’s SciDAC conference can be found at http://www.scidac.gov/Conference2007.

Large Applications, Distributing Computing
Keith Jackson and Dan Gunter were invited speakers at the conference, Challenges of Large Applications in Distributed Environments (GLADE), which took place this month in Monterey.

Jackson, head of the Advanced Application Interface Technologies Group in CRD, spoke about the remote analysis of large-scale data. Gunter, in the Collaborative Computing Technologies Group, spoke about troubleshooting data movement in his presentation.

Both scientists also took part in a panel discussion about data challenges for running large applications in distributed environments.