The National Institute for Computational Sciences

Storage Policy

Types of Storage

We have three file systems available to NICS users: home directories, system global temporary directories, and HPSS directories.

Home Directories

Home directories for each user are mounted on NICS systems via the Network File Service. This is online disk space intended for permanent, frequently used storage and is backed up on a daily basis. This file system does not generally provide the input/output (I/O) performance required by most jobs. The system global area is recommended for all I/O-intensive work.

System Global Temporary Directories (Work Directories)

Separate system global temporary directories are provided on each system. On Kraken, this is the Lustre file system. This is a large, fast disk area intended for global access to temporary storage, for example, to hold output generated by a user’s job. It is currently not backed up, and files that have not been accessed within 30 days are eligible to be purged. Our intention is to maintain these file systems so there is always a large amount of scratch space available for executing jobs. Users should move files that are not actively being used to HPSS.

Space Allocations

Home Directories

A research account is entitled to 2GB in its home directory. For projects with special requirements, we will consider extensions of this limit on a case-by-case basis.

System Global Temporary Directories (Work Directories)

Data in a system global file system should be present if needed or produced by a running, queued, or recently completed job. Files should not be retained in this file system and should be migrated to HPSS as soon as the files are not actively being used. Because of the working-directory character of the system global file system, files are automatically purged on a regular basis. Files that have not been accessed within 30 days are eligible for purging.


If a file system runs out of or gets low on space, user data on that file system will be subject to involuntary deletion without prior notice.

Consequences of Abuse

Storage usage will periodically be monitored. If time permits, first offenders will be warned to clean up their space. Ignoring these warnings will result in loss of access privileges.