Getting prepared for the LHC Run2: the PIC Tier-1 case

The Large Hadron Collider (LHC) experiments will collect unprecedented data volumes in the next Physics run, with high pile-up collisions resulting in events that require a complex processing. Hence, the collaborations have been required to update their Computing Models to optimize the use of the available resources and control the growth of resources, in the midst of widespread funding restrictions, without penalizing any of the Physics objectives. The changes in computing for Run2 represent significant efforts for the collaborations, as well as significant repercussions on how the WLCG sites are built and operated. This paper focuses on these changes, and how they have been implemented and integrated in the Spanish WLCG Tier-1 centre at Port d’Informació Cient́ıfica (PIC), which serves the ATLAS, CMS and LHCb experiments. The approach to adapt a multi-VO site to the new requirements, while maintaining top reliability levels for all the experiments, is as well presented. Additionally, a description of work done to reduce the operational and maintenance costs of the Spanish Tier-1 centre, in agreement with the expectations from WLCG, is provided.