Speaker
J-P. Baud
(CERN)
Description
LCG-2 is the collective name for the set of middleware released for
use on the LHC Computing Grid in December 2003. This middleware,
based on LCG-1, had already several improvements in the Data
Management area. These included the introduction of the Grid File
Access Library(GFAL), a POSIX-like I/O Interface, along with MSS
integration via the Storage Resource Manager(SRM)interface.
LCG-2 was used in the Spring 2004 data challenges by all four LHC
experiments. This produced the first useful feedback on scalability
and functionality problems in the middleware, especially with regards
to data management.
One of the key goals for the Data Challenges in 2004 is to show that
the LCG can handle the data for the LHC, even if the computing model
is still quite simple. In light of the feedback from the data
challenges, and in conjunction with the LHC experiments, a strategy
for the improvements required in the data management area was
developed. The aim of these improvements was to allow both easier
interaction and better performance from the experiment frameworks and
other middleware such as POOL.
In this talk, we will first introduce the design of the current data
management solution in LCG-2. We will cover the problems and issues
highlighted by the data challenges, as well as the strategy for the
required improvements to allow LCG-2 to handle effectively data
management at LCG volumes. In particular, we will highlight the new
APIs provided, and the integration of GFAL and the EDG Replica
Manager functionality with ROOT.