ATLASCM · Study and validation of the computing model for the atlas experiment
FP6 — Marie Curie Actions (Human Resources and Mobility)
- Duration
- 2005-04-01 → 2007-03-31
- EU contribution
- €173,832
- Participants
- 1
- Scheme
- EIF
Lines connect the coordinator with its partners.
Results in brief
Final Activity Report Summary - ATLASCM (Study and validation of the computing model for the Atlas experiment)
The Large hadron collider (LHC) at the European organisation for nuclear research (CERN) was planned to start data acquisition in 2008. The 'A toroidal LHC apparatus' (ATLAS) experiment was preparing for the data handling and analysis via a series of data challenges and production exercises to validate its computing model and provide useful samples of data for detector and physics studies. The ATLAS production system was successfully used to run production of simulation data at an unprecedented scale. Up to 50 000 jobs were processed by the system on more than 150 sites in one day. In this work, we demonstrated the capability of such a system for user analysis. This experience would allow us to compare the execution of analysis task using such a system versus using direct submission to the infrastructure. Compared to direct submission to the infrastructure we could observe a more robust execution and we were also profiting from the system advanced monitoring capabilities. A drawback was that the system represented an additional infrastructure element which had to be operated by the experiment. For ATLAS, as well as for other experiments, it was therefore a question to evaluate the advantages of using such a system for user analysis with the additional effort necessary to operate it as a service for its users. Distributed analysis in ATLAS was still in progress by the time of the project completion. With the start-up of LHC we expected a dramatic increase in data volume. This would therefore require the general ATLAS user to utilise grid resources to perform his analysis.
Data: CORDIS, © European Union
Project objective
The ATLAS experiment is a large detector for the study of high-energy proton-proton collisions at the Large Hadron Collider (LHC), presently under construction at the European Organization for Nuclear Research CERN and scheduled to start operation in 2007. In the ATLAS Computing Model, after reduction of the data by the online trigger processor farms, the volume of data recorded for offline reconstruction and analysis will be of the order of 1PB (1015 bytes) per year.The present proposal aims at a major contribution to the understanding, the development, the validation and the deployment of the ATLAS Computing Model that will be based on GRID technology. Part of the project will be to participate to the development of the software infrastructure needed for the production chain and the physics analysis. The conclusion of the work will be the demonstration of the full ATLAS data analysis chain in a large-scale GRID production infrastructure.The study and validation of the Computing Model started two years ago and will continue for few years in the context of the so-called Data Challenges (DC). DC1 was conducted during 2002-2003; the main achieved goals were to put in place the production infrastructure in a real worldwide collaborative effort and to gain a lot of experience in exercising an ATLAS wide production model. The analysis part of the general Computing Model was not exercised in DC1.The focus of DC2-3, planned for 2004-05, is on testing the Computing Model itself and most importantly the tier-0 part, which aims at the reconstruction of the events just after they come out of the data taking chain. It also include an analysis phase intended to test the distributed analysis parts of the Computing Model, the schedule of this phase is still under discussion since a LHC collaborative effort is being organized in the context of the LHC Computing Grid project (LCG).
Original text from CORDIS.
Participants
- EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH · GENEVECoordinatorSwitzerland
Links
Data: CORDIS, © European Union