Speaker
Mr
Sylvain Reynaud
(IN2P3/CNRS)
Description
It is broadly admitted that grid technologies have to deal with heterogeneity in both
computational and storage resources. In the context of grid operations, heterogeneity
is also a major concern, especially for worldwide grid projects as LCG and EGEE.
Indeed, the usage of various technologies, protocols and data formats induces
complexity. As learned from our experience on participating to the collaborative
development of a tool set for LCG/EGEE operations, this complexity increases the risk
of unreliable code, lack of reactivity and a extremely low level of reusability.
To reduce these risks, we need an extensible tool for reliably aggregating
heterogeneous data sources, for executing cross data sources queries and for exposing
the collected information for several usages.
In this paper we present "Lavoisier", an extensible service for providing an unified
view of data collected from multiple heterogeneous data sources. This service
transforms the collected data and represents it as XML documents: this allows for
transparently and efficiently executing XSL queries on them. The service also exposes
the data through standard protocols and interfaces (WSRF). In addition, its
efficiency can be optimized by tuning the provided cache mechanisms, according to
both the characteristics and the usage profile of the data coming out of each source
(access frequency, amount of data, latency, ...). The consistency of the exposed data
can be ensured by specifying dependencies between the cached data.
We also present some cases where Lavoisier has proven effective, like the usage that
is now done by the "LCG/EGEE CIC portal" a central tool for the operations of the
LCG/EGEE grid infrastructure. We see how in this particular case, Lavoisier allowed
the portal developers to reduce its code complexity while increasing the number of
offered features and provided the possibility to serve the collected data to other
operations tools.
Primary author
Mr
Sylvain Reynaud
(IN2P3/CNRS)
Co-authors
Mr
Fabio Hernandez
(IN2P3/CNRS)
Mr
Gilles Mathieu
(IN2P3/CNRS)
Mr
Osman Aidel
(CS-SI)
Dr
Pierre Girard
(IN2P3/CNRS)
