Speaker
A. Vaniachine
(ANL)
Description
In the ATLAS Computing Model widely distributed applications require access to
terabytes of data stored in relational databases. In preparation for data taking,
the ATLAS experiment at the LHC has run a series of large-scale computational
exercises to test and validate multi-tier distributed data grid solutions under
development.
We present operational experience in ATLAS database services acquired in large-scale
computations run on a federation of grids harnessing the power of more than twenty
thousand processors. Among the lessons learned is the increase in fluctuations in
database server workloads due to the chaotic nature of grid computations. The
observed fluctuations in database access patterns are of a general nature and must
be addressed through services enabling dynamic and flexibly managed provisioning of
database resources. ATLAS is collaborating with the LCG 3D project and the OSG Edge
Services Framework activity in the development of such services.
ATLAS database services experience relevant to local CERN data taking operations is
also presented including the conditions data flow of ATLAS Combined Test Beam
operations, prototype Tier 0 scalability tests and event tag database operations.
Summary
ATLAS database services experience and lessons learned in large-scale hierarchical
multi-tier distributed computations is presented.
Primary authors
A. Nairz
(CERN)
A. Vaniachine
(ANL)
D. Malon
(ANL)
F. Zema
(CERN)
G. Gieraltowski
(ANL)
G. Poulard
(CERN)
J. Cranshaw
(ANL)
K. Karr
(ANL)
L. Goossens
(CERN)
N. Barros
(CERN)
P. Nevski
(BNL)
R. Hawkings
(CERN)
T. Wenaus
(BNL)
Yu. Shapiro
(CERN)
Yu. Smirnov
(BNL)
