Software Distribution

Software Distribution is based on the well-known CernVM-File System (CernVM-FS), providing a scalable, reliable and low- maintenance software distribution service. It was developed to assist High Energy Physics (HEP) collaborations to deploy software on the worldwide- distributed computing infrastructure used to run data processing applications. CernVM-FS is implemented as a POSIX read-only file system in user space (a FUSE module). Files and directories are hosted on standard web servers and mounted in the universal namespace /cvmfs.

Software usually comprises many small files that are frequently opened and read as a whole. Furthermore, software includes frequent look-ups for files in multiple directories when search paths are examined. Through aggressive caching and reduction of latency, CernVM-FS facilitates deployment of the software, necessary to process experiment data, on distributed computing infrastructures. It replaces package managers and shared software areas on cluster file systems.