FileFamilies

Introduction

A file family is a set of files which are grouped exclusively on the same set of tapes. File families are used to indicate files that may be treated differently during data-handling operations. This might include tape library location, groupings for migration, deletion, or copy offsite, groupings for access priority or dCache location or lifetime on disk. For example, we expect to group raw data, reconstructed data, and simulations on different sets of tapes.

List

All the files of a file family are grouped exclusively on the same set of tapes. This creates different categories of physical tapes.

Here are the mu2e file families. You should be familiar with this list if you are uploading files to tape, but the general user reading files does not need to understand this list.

• phy-sim Monte Carlo simulated or reconstructed art files. These are official collaboration samples only, originated, produced, validated, and documented by physics groups intended for long-term use by many collabrators. Examples are the TDR and CD3 samples. The username associated with the files will be the production username "mu2e".
• phy-nts non-art format ntuples of phy-sim
• phy-etc configuration files, tarballs of log files, backups, and other files
• usr-sim Monte Carlo simulated or reconstructed art files. These samples are produced by one or a few individuals for use in their personal studies. They are probably for short-term use, not documented publically, and not used by many collaborators. The username associated with these files will be the person most likely to understand how they were created and how they should be used if questions come up a year or two later - the intellectual owner of the data.
• usr-nts Non-art format ntuples of usr-sim
• usr-etc Other user-created tarballs of log files, backups
• tst-cos Testbeam and cosmic data created before commissioning. This would include raw data formats as well as various possible derived formats and tarballs

For real data taking, more file families will be created to hold raw data, reconstructed data, and ntuples, etc.

When uploading files, you will need to specify the file family. Collaboration production will use "phy-*", users will use usr-sim for Monte Carlo art files, usr-nts for ntuples, and usr-etc for tarballs and anything else.