CHEP 06

The GridPP metadata group: metadata in a Grid era.

15 Feb 2006, 09:00

9h 10m

Tata Institute of Fundamental Research

poster Grid middleware and e-Infrastructure operation Poster

Speaker

Dr Paul Millar (GridPP)

Description

Continuing the UK's strong involvement with Grid computing, the GridPP2 project (2004--2007) has established a group to investigate the use of metadata within HEP Grid computing. Three posts (based at Glasgow) are dedicated to metadata, but the group includes others working for CERN, various LHC experiments, EGEE and further afield. An important aspect of the group's work is to provide a forum in which all those working on metadata services can be informed of each others work within this area. To this end, the group has various collaborative resources, monthly meetings and annual workshops. One of the first tasks undertaken by the group was reviewing a disparate collection of general HEP use-cases documents, identifying the corresponding requirements on any metadata service and consolidate these as metadata use-cases. This work is available as the paper "unlucky for some-the thirteen core use cases of HEP metadata." Storing metadata is a common issue amongst projects. Projects have proposed different solutions, based on various relational database schemata. The metadata group reviewed these schemata and a paper summarising the results was published. With any metadata service, one must monitor available servers, detect clients that cause surges in demand and allow remote experts to diagnose problems. The group has produced a requirements document for such monitoring and is helping implement a metadata monitoring system. In collaboration with LCG and EGEE, the metadata group helped establish a common interface for querying a metadata service. This interface has been adopted by several metadata servers. Work is ongoing in "Gridifying" existing tools, for example, by adding an authentication and authorisation framework with the AMI metadata server by integrating work from the VOMS project. We will present a summary of the work achieved to date and detail our plans for the future.