Speaker
Sasha Vanyashin
(Argonne National Laboratory)
Description
ATLAS event data processing requires access to non-event data (detector conditions, calibrations, etc.) stored in relational databases. The database-resident data are critical for the event data reconstruction processing steps and are often required for user analysis. A main focus of ATLAS database operations is on the worldwide distribution of the Conditions DB data, which are necessary for every data processing job. Since the Conditions DB is critical for operations with real data, we have developed a system where a different technology can be used as a redundant backup. Redundant database operations infrastructure fully satisfies the requirements of ATLAS reprocessing, which has been demonstrated on a scale of 1B database queries during the reprocessing campaign of 0.5 PB of single-beam and cosmics data on the Grid. To collect experience and provide input for a best choice of technologies, several promising options for efficient database access in user analysis are undergoing evaluation and testing. We present the ATLAS experience with scalable database access technologies and describe our approach for prevention of database access bottlenecks in a Grid computing environment.
Authors
James Herbert Cochran Jr
(Iowa State University)
Sasha Vanyashin
(Argonne National Laboratory)
