D. Rebatto (INFN - MILANO)
In this paper we present an overview of the implementation of the LCG interface for the ATLAS production system. In order to take profit of the features provided by DataGRID software, on which LCG is based, we implemented a Python module, seamless integrated into the Workload Management System, which can be used as an object-oriented API to the submission services. On top of it we implemented Lexor,an executor component conforming to the pull/push model designed by the DC2 production system team. It pulls job descriptions from the supervisor component and uses them to create job objects, which in turn are submitted to the Grid. All the typical Grid operations (match-making with respect to input data location, registration of output data in the replica catalog, workload balancing) are performed by the underlying middleware, while interactions with ATLAS metadata catalog and the production database are granted by the integration with the Data Management System (Don Quijote) client module and via XML messages to the production supervisor (Windmill).