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In this issue:
Collaboration Meeting Explores BaBar Strategy from Data Preservation to Dark Higgs Search
Lab Management Seeks Your Input: SLAC Survey Launched Today
Save the Date: SLAC Holiday Party Wednesday, December 16
Colloquium Today: Evolutions of Parallel Processing Computing—The Rise of Throughput Computing

SLAC Today

Monday - November 9, 2009

Collaboration Meeting Explores BaBar Strategy from Data Preservation to Dark Higgs Search

(Photo - BaBar Collaboration Meeting)
Collaboration members attend a talk in Panofsky Auditorium about dark matter detection using data from the BaBar experiment. (Photo by Adam Mann.)

The BaBar collaboration wrapped up last Thursday after over 150 team members converged at SLAC to discuss ongoing physics analysis, plan for long term data access during their archival period and celebrate a record 400 published papers.

"Such high attendance is proof that physicists remain strongly committed to the collaboration," said spokesman Francois Le Diberder, "Meetings were fueled with passion to discuss physics issues in depth."

Le Diberder considers the meeting a great success, which signals very good health for the BaBar Collaboration.

The meeting's parallel and plenary sessions were mainly devoted to presenting data analysis conducted in the last months. The data collection phase of BaBar ended in 2008 and the collaboration is now focused on the analysis of this very rich data set. Most interestingly, theoreticians have proposed that evidence of dark matter may currently be lurking in BaBar's data.  Read more...

Lab Management Seeks Your Input:
SLAC Survey Launched Today

Please take a few minutes to complete this survey on the organizational culture at the SLAC National Accelerator Laboratory. For the purpose of this survey, the term "organizational culture" refers to the status of activities that support the science mission throughout the laboratory. Basically, organizational culture refers to the worker’s "opinions, beliefs, and expectations" on how work is accomplished, including mission support activities such as safety and health; environmental protection; work planning and control; and sound financial and project management, contracts and legal, purchasing, facilities management and human resource management services. For example:

  • Do we place schedule in front of safety?
  • Does our training match the type of activities performed?
  • Do we value the individual?
  • Do we have a culture that values the "hero" over well-planned work?

The survey will be available online through November 20. We welcome your feedback, and your answers will be kept confidential. Thank you for your participation.

(Image - wreath)

Save the Date: SLAC Holiday Party Wednesday, December 16

Mark your calendars now for the SLAC holiday celebration, scheduled for Wednesday, December 16, from 11 a.m. to 1 p.m. All SLAC employees are invited to celebrate the holiday season with a scrumptious buffet luncheon. Watch SLAC Today for further details.

If you are interested in serving on the holiday committee, contact Charlotte Carlson in the Human Resources office (x2265). Volunteers wanted!

Colloquium Today: Evolutions of Parallel Processing Computing—The Rise of Throughput Computing

(Image - SLAC Colloquium banner)

All are invited to Kavli Auditorium at 4:15 p.m. today to hear chip maker NVIDIA's Chief Scientist William Dally present a colloquium on the development of parallel processing computing.

Advances in semiconductor technology over the last decades have opened up many new possibilities in parallel processing architecture. The technologies and architectures of the early supercomputers have evolved towards machines that support a combination of data- and thread-level parallelism and have a deep memory hierarchy. There is a tension between these emerging parallel machines and today’s commodity processor architecture.

Most commodity processors have limitations in two critical aspects of machine organization: parallel execution and hierarchical memory organization. These processors present to the programmer an illusion of sequential execution and uniform, flat memory. The evolution of these sequential, latency-optimized processors is at an end, and their performance is increasing only slowly over time. In contrast, the performance of throughput-optimized processors, such as Graphics Processing Units (GPUs), continues to increase and scale at historical rates. Throughput processors embrace, rather than deny, parallelism and memory hierarchy to realize their performance and efficiency advantage compared to conventional processors. Throughput processors have hundreds of cores today and will have thousands of cores by 2015. They will deliver most of the performance, and most of the user value, in future computer systems.

This talk will discuss some of the challenges and opportunities in the architecture and programming of future throughput processors. In these processors, performance derives from parallelism and efficiency derives from tight local coupling of computing and memory resources. Parallelism can take advantage of the plentiful and inexpensive arithmetic units in a throughput processor. Without locality, however, bandwidth quickly becomes a bottleneck. Communication bandwidth, not arithmetic power, is the critical resource in a modern computing system that dominates cost, performance, and power. This talk will discuss exploitation of parallelism and locality with examples drawn from the Imagine and Merrimac projects, from NVIDIA GPUs, and from three generations of stream programming systems.

The colloquium is free and open to all.

Next Monday's colloquium will return to Panofsky Auditorium, with Stanford University Consulting Professor Richard Dasher, director of the U.S.-Asia Technology Management Center and executive director of the Center for Integrated Systems at Stanford.


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