Enabling HPC systems for HEP: the INFN-CINECA Experience

In this report we want to describe a successful integration exercise between CINECA (PRACE Tier-0) Marconi KNL system and LHC processing. A production-level system has been deployed using a 30 Mhours grant from the 18th Call for PRACE Project Access; thanks to CINECA, more than 3x the granted hours were eventually made available. Modifications at multiple levels were needed: on experiments' WMS layers, on site level access policies and routing, on virtualization. The success of the integration process paves the way to integration with additional local systems, and in general shows how the requirements of a HPC center can coexist with the needs from data intensive, complex distributed workflows.