BNL Computing Information for USQCD Users

Tape archive system at BNL has been recently (as of Sep. 2025) migrated to HPSSFS. Direct access is available by logging on to dtn03 from one of ic2submit nodes. HPSSFS is mounted at /hpss/lqcd/archive/ (for short term data) and /hpss/lqcd-long-term/archive (for long term data). After some time set by the migration policy, the files will be written to tape. Both copying to and retrieval from tape is done by 'cp' command, similar to regular disk file copies, except for the time delay to mount the tape.

As of 2024-2025 allocation year, USQCD has 5.0PB (~3.7PB long term, ~1.3PB short tmer) of data stored on this system.  This USQCD storage is apportioned between users by the USQCD SPC.  The USQCD Liaison helps to allocate and adjust storage for users during the allocation year, as their needs vary.

The policy governing the tape archive system are:

• Users should request creation and/or access to the project directory in the archive by filing a ticket at SDCC. Please include the names of the project and the PI in the ticket.
• Users are strongly encouraged to keep the size of the files written to the tapes to be larger than 1GBytes. If you have smaller files, please tar them up. If LQCD users write files smaller than this, the access time to restore files from tape will be large, due to time spent seeking for small files on the tape drives.
• It is strongly discouraged to rename or change files after they are written. Doing so will cause duplication of files and lost storage space. Please be thoughtful about what you put on tape.