Speaker
Dr
Stephen Burke
(Rutherford Appleton Laboratory, UK)
Description
A common information schema for the description of Grid resources and services
is an essential requirement for interoperating Grid infrastructures, and its
implementation interacts with every Grid component. In this context, the GLUE
information schema was originally defined in 2002 as a joint project between
the European DataGrid and DataTAG projects and the US iVDGL (the
predecessors of the current EGEE/LCG and OSG Grids). It has since had three
backward-compatible upgrades, with the latest version (1.3) being deployed
this year. The schema has major components to describe Computing and
Storage Elements, and also generic Service and Site information. It has been
used extensively in the LCG/EGEE Grid, for job submission, data management,
service discovery and monitoring. In this paper we present the experience
gained over the last five years, highlighting both successes and problems. In
particular, we consider the importance of having a clear definition of schema
attributes; the construction of standard information providers and difficulties
encountered in mapping an abstract schema to diverse real systems; the
configuration of publication in a way which suits system managers and the
varying characteristics of Grid sites; the validation of published information; the
ways in which information can be used (and misused) by Grid services and
users; and issues related to managing schema upgrades in a large distributed
system.
Authors
Mr
Laurence Field
(CERN, Geneva, Switzerland)
Dr
Sergio Andreozzi
(INFN-CNAF, Bologna, Italy)
Dr
Stephen Burke
(Rutherford Appleton Laboratory, UK)
