The Leading Source for Global News and Information Covering the Ecosystem of High Productivity Computing
July 14, 2008
Researchers Conduct Breakthrough Fusion Simulation
GTC consumes 93 percent of 263TF Jaguar
July 14 -- A team of researchers from the University of California-Irvine (UCI), in conjunction with staff at Oak Ridge National Laboratory's National Center for Computational Sciences (NCCS), has just completed what it says is the largest run in fusion simulation history.
The team, led by Yong Xiao and Zhihong Lin of UCI, used 93 percent of the NCCS's flagship supercomputer Jaguar, a Cray XT4, with the classic fusion code GTC (Gyrokinetic Toroidal Code), the key production code of two fusion SciDAC projects (GPS-TTBP and GSEP).
The simulation primarily studied electron transport in ITER, a prototype fusion reactor now in development that is meant to test fusion's feasibility for commercial power production (because in ITER the fusion process will primarily heat electrons, electron transport will be more important compared to existing fusion devices). Fusion energy could one day provide the world with a cleaner, more abundant energy source with far fewer harmful emissions than fossil-fuel-burning power plants and fewer waste issues than current nuclear power production.
To successfully produce a fusion reaction, an extremely hot ionized gas known as a plasma must be confined magnetically for a sufficient period of time. Previous research has shown that heat transport for both the ions and the electrons in the plasma is far greater than theory predicts (the electron heat transport can be two orders of magnitude greater). This larger-than-expected heat transport could lead to confinement failure within one second, quickly rendering energy production impossible if reactor designs are not modified to accommodate it.
The researchers discovered, among other things, that for a device the size of ITER, the containment vessel will demonstrate GyroBohm scaling, meaning that the heat transport level is inversely proportional to the device size. In other words, the simulation supports the ITER design: a larger device will lead to more efficient confinement.
"The success of fusion research depends on good confinement of the burning plasma," said Xiao. "This simulation size is the one closest to ITER in terms of practical parameters and proper electron physics."
Because fusion simulation is such a complex process, today's leadership-class supercomputers such as Jaguar, with their fast CPU speeds and large memory, are an absolute necessity. GTC can effectively utilize large numbers of Jaguar's cores thanks to an efficient three-level parallelism (using both MPI and OpenMP) designed by Stephane Ethier (Princeton Plasma Physics Laboratory) and Zhihong Lin.
However, the huge amounts of data produced by fusion simulations can create I/O nightmares: in one GTC run, the team can produce terabytes of data (in this case 60TB). To address this potential bottleneck, the team used ADIOS, a set of library files that allows for easy and fast file input and output, developed mainly by the NCCS's Scott Klasky and Chen Jin and Georgia Tech's Jay Lofstead and Karsten Schwan.
"This huge amount of data needs fast and smooth file writing and reading," said Xiao. "With poor I/O, the file writing takes up precious computer time and the parallel file system on machines such as Jaguar can choke. With ADIOS, the I/O was vastly improved, consuming less than 3 percent of run time and allowing the researchers to write tens of terabytes of data smoothly without file system failure."
ADIOS is a good example of the symbiotic relationship between researchers and NCCS staff. "My experience with Cray and the NCCS has been very good," said Xiao. "The account and operation staffs are very accessible and responsible, which enabled us to run the GTC code with a total of 28,000 cores smoothly for two days. [The NCCS's] Scott Klasky provided an effective channel for technical communication between the science application team and the computational support team."
Despite the success of the recent simulation, there is still much work to be done. "Plasma turbulent transport is still an ongoing research area," said Xiao. However, each new simulation brings new data, which bring a revolutionary energy source one step closer to reality.
-----
Source: Scott Jones, National Center for Computational Sciences
Sponsored Links
Interview: Appro CEO Shares HPC Vision
Appro CEO Daniel Kim provides a glimpse into Appro's vision and opportunities for its supercomputer and high-performance cluster solutions.
RSS Feeds
Feeds by Topic
- Applications
- Developer Tools
- Interconnects
- Middleware
- Networks
- Processors
- Storage
- Systems
- Visualization
Feeds by Industry
Feeds by Content Type
Feature Articles
Computed Tomography Software Taps Into NVIDIA GPUs
Minnesota-based North Star Imaging, a firm that specializes in industrial X-rays for nondestructive testing and analysis, is employing NVIDIA GPUs to accelerate 3D renderings in their CT (computed tomography) software. Julien Noel, the company's CT product manager, says the exceptional computational power afforded by CUDA and Tesla hardware is increasing customer productivity and transforming their workflow.
Read More...
The Next Big Thing in Humanities, Arts and Social Science Computing: 18thConnect
For the humanities scholar who may have only recently mastered library and archival finding aids beyond the archaic card catalog, the possibility of retrieving source materials at the flash of a keystroke (well maybe a few...) is very heady stuff.
Read More...
HPC Clouds -- Alto Cirrus or Cumulonimbus
The "cloud" model of exporting user workload and services to remote, distributed and virtual environments is emerging as a powerful computing paradigm. Yet, one domain that challenges this model in its characteristics and needs is high performance computing.
Read More...
Top Headlines
Dawning 6000 to Use Chinese-Made Loongson Processor
Nov 28 | People's Daily Online | Currently under development, the Dawning 6000 HPC system will be based on the Chinese-made "Loongson" microprocessor. Read more...
Can Supercomputers Help Save the Economy?
Nov 27 | Computerworld | The use of supercomputers to increase the industrial might of the U.S. has amounted to little more than an asterisk from a financial standpoint in both the federal budget and the economy as a whole. Read more...
IBM to Establish 'Collaboratory' in Dublin
Nov 26 | Science Business | IBM is getting ready to set up a supercomputing research “collaboratory” in Dublin, Ireland. Read more...
Texan Prof Sees Big Future for Graphene Storage
Nov 25 | The Register | A Rice University professor believes that his proposed graphene arrays could be many times denser and faster than existing storage tech, and they'd be more reliable too. Read more...
Super Micro Computer: A One-Man, or at Least One-Family, Powerhouse
Nov 24 | The New York Times | Server maker Super Micro Computer lives by two principles: give customers what they want, and do it as fast as humanly possible. Read more...
Multimedia
Video White Paper: Architecting a Better Network Storage Solution
BlueArc's Titan architecture represents an evolutionary step in file servers by creating a hardware-based file system that can scale bandwidth, IOPS, and overall data capacity well beyond conventional software-based devices. With its ability to virtualize a massive storage pool of up to four usable petabytes of tiered storage, Titan can scale with growing data requirements, offering a competitive advantage for businesses, researchers, or other enterprises seeking to better manage data growth while still ensuring optimal performance.
Newsletters
Stay informed! Subscribe to HPCwire email Newsletters.
Get updates and insights on the High Productivity Computing industry delivered driectly to your inbox.
HPC Job Bank
-
Sr. Systems Developer/Engineer
Ohio State University -
HPC System Administration Specialist
Argonne National Laboratory - Visit the HPCwire Job Bank
Featured Events
-
February 24-27, 2009
TradeTech Architecture 2009
London England
-
April 13-16, 2009
Symposium 2009: LEAN, CLEAN, and GREEN
New York , NY
USA