Global Access to High Energy Physics Software with Parrot and CVMFS

Scientists searching for the Higgs boson have profited from Parrot's new support for the CernVM Filesystem (CVMFS), a network filesystem tailored to providing world-wide access to software installations. By using Parrot, CVMFS, and additional components integrated by the Any Data, Anytime, Anywhere project, physicists working in the Compact Muon Solenoid experiment have been able to create a uniform computing environment across the Open Science Grid. Instead of maintaining large software installations at each participating institution, Parrot is used to provide access to a single highly-available CVMFS installation of the software from which files are downloaded as needed and aggressively cached for efficiency. A pilot project at the University of Wisconsin has demonstrated the feasibility of this approach by exporting excess compute jobs to run in the Open Science Grid, opportunistically harnessing 370,000 CPU-hours across 15 sites with seamless access to 400 gigabytes of software in the Wisconsin CVMFS repository.
  
- Dan Bradley, University of Wisconsin and the Open Science Grid