CMS Offline software vs AFS

Friday 27 Mar 2015, 11:00 → 12:00 Europe/Zurich

6-2-25 (CERN)

CMS Offline Software vs AFS meeting 2015-03-27

Present: Giulio, Shahzad, Jan

• CMS Offline SW already started to reduce dependencies on AFS some time ago
• CMS Offline software is compiled locally (VM with CEPH blockdevice), builds do not depend on AFS
• release builds get pushed to CVMFS and AFS (and as locally-installable RPMs), via rsync
• integration builds are available on CVMFS, but due to the long delay (i.e hours) when pushing are preferrably accessed from AFS
• full migration out of AFS for CMS Offline software is feasible, needs at most O(weeks) of effort, timeline of a year would not cause any stress.

Other CMS use cases to consider:

• Desktop users will assume they can run CMS software without further setup. Need CVMFS to be available there, or need an easily-accessible CMS YUM repository.
  • Laptop users exists but are used to some extra steps in order to get the CMS software installed locally
• T0 has perhaps some special use cases (Dirk), same for DB (Andreas)
• expect many personal (work-related) and project websites to be on AFS, need list, need to announce migration and see whether all are OK on Drupal (or whatever IT recommends). In particular CGI scripting is required for several (example: "igprof reports")
• special: CMS has a GitHub shared caching object store on AFS (huge performance improvement over local checkouts. Could switch, but would need to see whether e.g faster block storage would help)