As preparations commence for the restart of the Large Hadron Collider (LHC), the world's most powerful particle accelerator, computing specialists around the world have been hard at work on one of the most important systems needed to support the scientific program of the LHC-the Worldwide LHC Computing Grid (WLCG).
After months of preparation and two intensive weeks of 24/7 operation, the LHC experiments are celebrating the achievement of a new set of goals aimed at demonstrating full readiness for the LHC data taking run expected to start later this year. The recent Scale Testing for the Experiment Programme '09 (STEP'09) was the first production demonstration involving all of the key computing elements from data taking through to analysis.
With the restart of the LHC only months away, one can expect a large increase in the number of Grid users: from several hundred unique users today to several thousand. Thus it is critical that the system be ready for maximum end-user efficiency and ease. STEP'09 included massive-scale testing of end-user analysis scenarios, including "community support" infrastructures, whereby the community is trained and enabled to be largely self-supporting, backed by a core of Grid application experts.
Michael Vetterli, physics professor at Simon Fraser University and TRIUMF, and the computing coordinator for ATLAS-Canada and the chair of the WLCG Collaboration Board, remarked: "STEP' 09 was not only the most complete test of the Grid to date, but it also exercised the support infrastructure. A number of new problems were brought to light, and it was gratifying to see that they were dealt with quickly and efficiently by the support team using the communication tools put in place. In Canada, networking is a major issue because of the distances involved both within the country itself as well as the main link to CERN in Europe"-the ATLAS Tier-1 Data Centre here at TRIUMF is connected to CERN via a dedicated light path some 12,000km long. "The network performed extremely well with large amounts of data transferred between the sites," said Vetterli, despite the potential problems that could arise during such testing.
These recent successes are significant for TRIUMF's ATLAS Tier-1 Data Centre. As one of a dozen Tier-1 centres in national computing facilities around the world, the Data Centre will participate in the storage and analysis of petabytes (millions of Gigabytes) of data generated by the ATLAS detector at CERN in Switzerland. ATLAS alone ran close to 1M analysis jobs and achieved 6GB per second of "Grid traffic", the equivalent of a DVD worth of data a second, sustained over long periods.
The ATLAS Canada Tier-1 Data Centre is funded by the Canada foundation for Innovation (CFI), the British Columbia Knowledge Development Fund (BCKDF), with significant in-kind contributions from TRIUMF and from the computing industry, notably IBM, in the form of discounts on hardware purchases. Networking resources essential for the TRIUMF facility are provided by CANARIE, BCNET and HEPNET Canada.
-- Meghan Magee, Communications Assistant
Based on CERN press release: http://press.web.cern.ch/press/PressReleases/Releases2009/PR11.09E.html