ATLAS DQ2 DELETION SERVICE

ATLAS DQ2 Deletion service is a sub system of the ATLAS Distributed Data Management (DDM) project DQ2. DDM DQ2 responsible for the replication, access and bookkeeping of ATLAS data across more than 130 distributed grid sites. It also enforces data management policies decided on by the collaboration and defined in the ATLAS computing model. Responsibility of ATLAS DQ2 Deletion service is serving deletion requests on the grid by interacting with grid middleware and the DQ2 catalogues. Furthermore, it also takes care of retry strategies, check-pointing transactions, load management and fault tolerance. In this talk special attention is paid to the technical details, which are used to achieve the high performance of service, accomplished without overloading either site storage, catalogues or other DQ2 components. Also specialty of database backend implementation will be described. Special section will be devote to the deletion monitoring service that allows operators a detailed view of the working system.