Speaker
Farida Fassi
(IFIC- Instituto de Fisica Corpuscular)
Description
The ATLAS experiment currently under construction at CERN's Large Hadron Collider
presents data processing requirements of an unprecedented scale. ATLAS will accrue
tens of petabytes of data per year, distributed around the world: the collaboration
comprises more than 1800 physicists from 150 institutions in 34 countries. The
Distributed Analysis (DA) system has the goal of enabling ATLAS physicists to perform
analysis on distributed data using distributed computing resources. Both data and
resources are widely distributed throughout the world at CERN and at ATLAS Tier-1 and
Tier-2 centers. Since DA system is of strategic importance there is a large
development activity going on in this area: the ATLAS production system has being
evolving to support the analysis jobs which will have a seamless access to all ATLAS
resource, as well as another activities that aim to support user analysis by
submitting directly to the separate grid infrastructures (Panda at OSG, direct
submission to LCG and Nordugrid). The test of DA functionality will be addressed in
the final Service Challenge 4 (SC4), in which the system will exposed to the expected
large number of final analysis users. The Spanish ATLAS Tier-2 facility formed by
IFIC, IFAE and UAM groups, is participating in several aspects of the Distributed
Analysis System. In support of the ATLAS DA activities the IFIC Tier-2 center has
developed and deployed a local computational facility which comprises many service
nodes, computational clusters and large scale disk and tape storage services. The
resources contribute to a variety of activities such as the analysis center facility
for the next SC4 in which the technical aspects of DA will be tested and evaluted. In
this paper we describe the ATLAS DA as well as we present our experience with the
deployment, maintenance and operation of the mencioned DA prototype from the whole
ATLAS collaboration and from the framework of the Spanish Tier-2 users point of view.
Author
Farida Fassi
(IFIC- Instituto de Fisica Corpuscular)
Co-author
Jose Salt
(IFIC)
