No. 35 (00123)

Family name : Andronico
Given name : Giuseppe
Affiliation : INFN Sezione di Catania 
Abbreviation : INFN - ITALY
E-mail address : giuseppe.andronico@ct.infn.it
Title : Grid portal based data management for Lattice QCD data
Authors : G.Andronico, R.Barbera, A.Falzone
Abstract : 
A Grid provides a set of coordinated services that efficiently make a
vailable all computational and mass storage resources distributed at a
geographic scale, in a secure, ubiquitous and transparent way, to all
members of multi-Institutional Virtual Organizations authorized to
utilize them.

The DataGrid Project (EDG, http://www.eu-datagrid.org), which is
currently entering the final phase of its three-years lifetime, is the
biggest Grid Project financed so far by the European Union and has
successfully deployed both a continental testbed and a complete series
of middle-ware services. The EDG testbed has been used by scientific
applications belonging to the realms to High Energy Physics,
Bio-medecine and Earth Observations.

In this contribution we describe the use of EDG data management Grid
services by a Lattice Quantum Chromo-Dynamics (LQCD) application. LQCD
simulations are aimed at building field configurations by means of which
one can "measure" observables. The generation of this configurations is
the more CPU time consuming part of a simulation job (about 12 hours of
1 TeraFlops computer for one configuration with dynamical fermions),
especially if some types of dynamical fermionic simulations are
included, and requires the availability of a huge mass storage (about
100MB for configuration, several hundreds of configurations per job).
In  order to help theoretical physicists to share these data, the
International Lattice Data GRID Project
(http://www.lqcd.org/ildg/tiki-index.php, http://www.lqcd.org/) has
developed, as a tool to enable the use of field configurations in a Grid
environment, a XML dialect called QCDML to describe these configurations
so that they can be browsed and searched on the Grid storage elements
where they have been saved at the end of simulation jobs.

We describe here the first version of a tool based on the DataGrid
middle-ware and on the GENIUS Grid portal (https://genius.ct.infn.it),
jointly developed by INFN and NICE s.r.l., which implements the
possibility for the user to store, search and browse field
configurations described by QCDML files.