Speaker
Description
The CernVM-Filesystem (CVMFS) is a global, read-only, on-demand filesystem optimized for software distribution. CVMFS is also a very efficient way of distributing container images and can be used with container runtimes such as Apptainer or Containerd to lazy-load images. The unpacked.cern.ch repository at CERN, a service that allows users to publish container images to CVMFS has become one of the fastest growing repositories, currently containing more than 8000 images and 90 million objects in backend storage.
In this contribution we discuss the challenges of managing a repository at this scale and the technical hurdles to improving service quality. In particular we show the possible improvements from moving to an implementation of the unpacker that does not store intermediate overlaid layers (“chains”) in the CVMFS repository.