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InTheLoop | 02.14.2011

February 14, 2011

Terabit Networks for Extreme Scale Science Workshop This Week

The DOE Office of Advanced Scientific Computing Research is sponsoring an invitation-only meeting on “Terabit Networks for Extreme Scale Science” on February 16 and 17 in Rockville, MD. Bill Johnston of ESnet is chair, and Inder Monga is one of seven co-chairs. Speakers from Berkeley Lab include:

  • ESnet – Energy Sciences Network: An update (Steve Cotter)
  • ESnet: Energy Sciences Network: Usage Patterns and Lessons Learned (Eli Dart)
  • Extreme Scale Computing and Networking Environment (John Shalf)

Chin Guok, Alex Sim, Brian Tierney, and Chris Tracy will also be participating.

“Father of Floating Point” William Kahan to give Feb. 15 Lecture

UC Berkeley Professor Emeritus William Kahan will describe “Needed Remedies for the Undebuggability of Large-Scale Floating-Point Computations in Science and Engineering” in a Computing Sciences seminar to be held at 11 am Tuesday, Feb. 15, in Bldg. 50B, Room 4205. (See the abstract below under “This Week’s Computing Sciences Seminars.”)

Kahan was the primary architect behind the IEEE 754-1985 standard for binary floating-point arithmetic, now more or less ubiquitous, and has been called “The Father of Floating Point,” since he was instrumental in creating the original IEEE 754 specification. Kahan received the Turing Award in 1989 for “his fundamental contributions to numerical analysis,” and was named an ACM Fellow in 1994. His other interests are sampled at http://www.eecs.berkeley.edu/~wkahan.

Trever Nightingale Joins CS Top 10 Safety Winners

Trever Nightingale of NERSC has been recognized with a SPOT Award for the best CS Safety Suggestion for September-December 2010. Nightingale reported a safety hazard involving installation of equipment in a rack. Go here for more information on current and past winners of the CS Top 10 Safety Competition. The submission deadline for the next award cycle is April 30.

Kennedy High School Students Visit NERSC

Eighteen students from Kennedy High School’s TechFutures Academy in Richmond paid a visit to NERSC on February 9. In addition to a brief introduction to supercomputers from NERSC’s User Services Group Lead, Katie Antypas, the students also got a lesson about how “Careers in Computer Science Save the World” from Associate Lab Director of Computing Sciences Kathy Yelick. One of the highlights of the visit was a tour of the facility’s computer room. See slideshow.

Advance Registration Open for Tapia Diversity in Computing Conference

Registration is now open for the 2011 Richard Tapia Celebration of Diversity in Computing Conference to be held April 3-5, 2011 in San Francisco. Early-bird discounts of $75 off the regular registration fees are available through Tuesday, March 8. Marking the 10th anniversary of the first Tapia conference, Tapia 2011 is centered around a series of presentations by distinguished speakers from industry and academia. Berkeley Lab Computing Sciences is a contributing supporter of the conference. Read more about the conference program here.

Volunteers Needed for PhatMath.com Math Social Network

The math social network PhatMath.com was recently named one of the Top 50 Social Sites for Educators and Academics. PhatMath.com provides free homework help to students in grades K-12 and college in 40 math courses. They are looking for more volunteers to serve as math coaches and mentors. If you’re interested, contact Dr. Iris Mack.

CITRIS Viewing Party Wednesday for IBM’s Watson on Jeopardy!

On Wednesday, February 16, the finale of the much anticipated Jeopardy! match featuring IBM’s Watson and the game show’s two most successful contestants, Ken Jennings and Brad Rutter, will air live on national television.

You are invited to a viewing party beginning with refreshments at 5:30 pm. At 6:15 pm, the festivities will begin at the Banatao Auditorium at Sutardja Dai Hall on the UC Berkeley campus with an explanation/discussion of the game of the Jeopardy! and the Watson computing system. Three distinguished panelists and a moderator will also comment on the game, which will be aired from 7:00–7:30 pm in the auditorium. Seating is first come, first served.

The first two rounds of Watson vs. humans will be televised tonight and tomorrow, Feb. 14–15. Watson’s software, called DeepQA, incorporates natural language processing, machine learning, knowledge representation, and deep analytics, as described in HPCwire. In dozens of practice rounds against former Jeopardy! champs, the computer was beating the humans with a 65 percent win rate.

Monday Night PlayGround and MSRI Present “Kingdom of Number”

Monday Night PlayGround (now in its 17th season) is a monthly presentation of six short plays written on a common theme. On Monday, February 21, the theme will be a mathematical one, “Kingdom of Number” (from the first line of W. H. Auden’s poem “Numbers and Faces”).

On February 9, a group of mathematicians at the Mathematical Sciences Research Institute (MSRI) met with the PlayGround pool of playwrights to talk about numbers, how mathematicians think about them, and the often surprising ways in which concepts of number appear in our culture and in nature. The playwrights went away to think about the dramatic possibilities that the topic suggested. They each have five days to write a short play inspired by the topic, and the best six of the resulting plays will be presented starting at 8:00 pm on February 21 at the Berkeley Repertory Theatre, 2025 Addison Street. There will be a pre-show discussion at 7:10 pm. Ticket information can be found here.

This Week’s Computing Sciences Seminars

Needed Remedies for the Undebuggability of Large-Scale Floating-Point Computations in Science and Engineering
Tuesday, February 15, 11:00 am–12:00 pm, 50B-4205
William Kahan, University of California, Berkeley

Despite almost universal conformity to IEEE Standard 754, floating-point arithmetic still teems with mysteries and misconceptions, some still enshrined in programming languages. Roundoff, invisible in programs’ texts, occasionally causes the worst anomalies: results unobviously wrong enough to mislead and almost always misdiagnosed.

Also misdiagnosed more often than not is misbehavior precipitated by arithmetic exceptions, like over/underflow and division-by-zero, treated as programmers’ errors deserving disruption of the program’s intended path of control. Ample instances of misdiagnoses will be presented.

Must computing professionals acquiesce to a resurgent superstition that numerical software is inevitably buggy, like Microsoft’s Windows?

Developers and users of numerical software must demand but cannot by themselves produce the peculiar tools needed to debug floating-point anomalies whenever these are suspected. The tools must come from Computer Science departments; nobody else in industry and academia has motive and opportunity. Help is needed from designers and implementers of hardware, of programming languages, and of the debuggers in software development environments to collaborate on features that will help to localize an anomaly’s cause to a comparatively short segment of code, when possible. These features will be explained. Some have existed in hardware for decades but are atrophying for lack of employment.

Collateral reading: http://www.cs.berkeley.edu/~wkahan/Mindless.pdf and http://www.cs.berkeley.edu/~wkahan/JAVAhurt.pdf

LAPACK Seminar: Solving Large-Scale Eigenvalue Problems in Nuclei Structure Calculation
Wednesday, February 16, 11:10 am–12:00 pm, 380 Soda Hall, UC Berkeley
Chao Yang, Computational Research Division, LBNL

One of the emerging computational approaches in nuclear physics is the configuration interaction (CI) method for solving the nuclear many-body problem. Like other quantum mechanics calculations, the basic computational problem is an eigenvalue problem. In many cases, one is interested in obtaining a few smallest eigenvalues and the corresponding eigenfunctions of a many-body Hamiltonian. In some applications, one may be interested in computing a relatively large number of small eigenvalues with a prescribed total angular momentum J or certain properties of a nucleus pertaining to a fixed J value. This type of calculation can be done by a simultaneous diagonalization of the Hamiltonian and the total angular momentum square operator. Although eigenvalue calculation is a well studied subject in numerical linear algebra, solving large-scale eigenvalue problems on high performance computers consisting of many thousands of processing units is challenging. I will describe a number of techniques for achieving good performance in nuclear CI calculations.

Link of the Week: Einstein and Car Batteries

Albert Einstein never learned to drive. He thought it too complicated and in any case he preferred walking. What he did not know—indeed, what no one knew until now—is that most cars would not work without the intervention of one of his most famous discoveries, the special theory of relativity. According to the calculations of Pekka Pyykko of the University of Helsinki and his colleagues, the familiar lead-acid battery that sits under a car’s hood and provides the oomph to get the engine turning owes its ability to do so to special relativity. Read more.

About Computing Sciences at Berkeley Lab

The Lawrence Berkeley National Laboratory (Berkeley Lab) Computing Sciences organization provides the computing and networking resources and expertise critical to advancing the Department of Energy's research missions: developing new energy sources, improving energy efficiency, developing new materials and increasing our understanding of ourselves, our world and our universe.

ESnet, the Energy Sciences Network, provides the high-bandwidth, reliable connections that link scientists at 40 DOE research sites to each other and to experimental facilities and supercomputing centers around the country. The National Energy Research Scientific Computing Center (NERSC) powers the discoveries of 7,000-plus scientists at national laboratories and universities, including those at Berkeley Lab's Computational Research Division (CRD). CRD conducts research and development in mathematical modeling and simulation, algorithm design, data storage, management and analysis, computer system architecture and high-performance software implementation. NERSC and ESnet are Department of Energy Office of Science User Facilities.

Lawrence Berkeley National Laboratory addresses the world's most urgent scientific challenges by advancing sustainable energy, protecting human health, creating new materials, and revealing the origin and fate of the universe. Founded in 1931, Berkeley Lab's scientific expertise has been recognized with 13 Nobel prizes. The University of California manages Berkeley Lab for the DOE’s Office of Science.

DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.