Experiences with PROOF in ATLAS

Philippe CALFAYAN
U Munich / ATLAS

The PROOF (Parallel ROOT Facility) library is designed to perform
parallelized ROOT-based analyses with a possibly heterogeneous cluster of
computers. The configuration and monitoring of PROOF have been carried out
using the Grid-Computing environments dedicated to the ATLAS experiment.
A PROOF cluster hosted at the Leibniz Rechenzentrum (LRZ) and consisting of
a scalable amount of working nodes has been exploited in order to conduct
the performance tests in the case of interactive ATLAS analyses. Scenarios
of various complexities have been considered to exercise PROOF with ATLAS
data, and evaluate its utilization in actual conditions.
The scalability of PROOF has been investigated by varying the number of
parallelized processing units, and the amount of simultaneous users.
Storage strategies based on local files, dCache, and Lustre have been
experimented.