Managing the CMS Data and Monte Carlo Processing during LHC Run 2

Abstract

In order to cope with the challenges expected during the LHC Run 2 CMS put in a number of enhancements into the main software packages and the tools used for centrally managed processing. In the presentation we will highlight these improvements that allow CMS to deal with the increased trigger output rate, the increased pileup and the evolution in computing technology. The overall system aims at high flexibility, improved operational flexibility and largely automated procedures. The tight coupling of workflow classes to types of sites has been drastically relaxed. Reliable and high-performing networking between most of the computing sites and the successful deployment of a data-federation allow the execution of workflows using remote data access. That required the development of a largely automatized system to assign workflows and to handle necessary pre-staging of data. Another step towards flexibility has been the introduction of one large global HTCondor Pool for all types of processing workflows and analysis jobs. Besides classical Grid resources also some opportunistic resources as well as Cloud resources have been integrated into that Pool, which gives reach to more than 200k CPU cores.