Last week at ISC Cloud 2010, Ulrich Schwickerath, from the CERN IT-PES/PS Group, presented the last benchmarking results of CERN’s OpenNebula cloud for batch processing. The batch computing farm makes a critical part of the CERN data centre. By making use of the new IaaS cloud, both the virtual machine provisioning system and the batch application itself have been tested extensively at large scale. The results show OpenNebula managing 16,000 virtual machines to support a virtualized computing cluster that executes 400,000 jobs.