DDM Site Services: A Solution for Global Replication of HEP Data
Fernando Harald Barreiro Megino · 2012
On behalf of the ATLAS CollaborationThe ATLAS Distributed Data Management (DDM) is the system built on top of the World Wide LHC Computing Grid (WLCG) middleware and is responsible for the organization of the multi-Petabyte ATLAS data across more than 100 distributed grid sites.One particular component of the system -the DDM Site Services -is the set of agents responsible for the discovery and placement of ATLAS data between sites.DDM Site Services manage aggregated throughputs of over 6GB/s or one million file-transfers a day and have to work with extremely high reliability and availability.This contribution reports on the production experience acquired during the last 2 years of LHC data taking and show the changes, adaptations and improvements that we implemented on the system to guarantee a flawless service.In addition we will give an update on the service and activity monitoring frameworks that publish the information needed by shifters and experts.Since the implementation is based on common grid middleware, these proceedings can be interesting for any community that is planning their move to the grid or would like to benefit from the approach of one of the largest heavy user communities.