The Tier2 Computing Facility at the California Institute of Technology provides computing support for the international scientific community. Our facility is part of the Data Grid Hierarchy set-up for Large Hadron Collider experiments. It serves as an intermediary between the Tier1 center at Fermilab and universities in Southern California. Our primary focus is computing support for the Compact Muon Solenoid experiment. We provide resources for other high energy physics experiments as well as general-purpose scientific computing on the Open Science Grid. Our group is an active member of the Open Science Grid Consortium.
The Caltech Tier2 Center is located primarily in the Powell-Booth Laboratory for Computational Science, with additional production and lab space in Lauritsen Hall. At present, the Tier2 Center consists of a primary cluster attached to the Open Science Grid (for large-scale simulation and reconstruction batch use) and CMS Production Analysis. Additional opportunistic resources are provided by the local cluster that serves users in the High Energy Physics department in Lauritsen Hall. Caltech HPC Resources are also used to extend the Caltech Tier2 Resources and increase the demand of growing CPU needs.
The Tier2 facility is connected from the Caltech campus to downtown Los Angeles at 100Gb via CENIC, and peers with the Pacific Research Platform and the Department of Energy’s ESnet. The core network for the racks in both Powell-Booth and Lauritsen is 40Gb, with a 100Gb link between the buildings. Most compute/storage hosts are connected locally at 1Gb/10Gb, but starting late 2016 this has changed to 10Gb/40Gb respectively.
Physically, the Tier2 clusters are housed in 18 42U racks.