User-Centric Data Storage

The following table summarizes user-centric storage areas available on OLCF resources and lists relevant polices.

User-Centric Storage Areas

Area Path Type Permissions Quota Backups Purged Retention
User Home $HOME NFS User-controlled 50 GB Yes No 90 days
User Archive /home/$USER HPSS User-controlled 2 TB [1] No No 90 days

footnotes

[1]In addition, there is a quota/limit of 2,000 files on this directory.

User Home Directories (NFS)

The environment variable $HOME will always point to your current home directory. It is recommended, where possible, that you use this variable to reference your home directory. In cases in which using $HOME is not feasible, it is recommended that you use /ccs/home/$USER.

Users should note that since this is an NFS-mounted filesystem, its performance will not be as high as other filesystems.

User Home Quotas

Quotas are enforced on user home directories. To request an increased quota, contact the OLCF User Assistance Center. To view your current quota and usage, use the quota command:

$ quota -Qs
Disk quotas for user usrid (uid 12345):
     Filesystem  blocks   quota   limit   grace   files   quota   limit   grace
nccsfiler1a.ccs.ornl.gov:/vol/home
                  4858M   5000M   5000M           29379   4295m   4295m

User Home Permissions

The default permissions for user home directories are 0750 (full access to the user, read and execute for the group). Users have the ability to change permissions on their home directories, although it is recommended that permissions be set to as restrictive as possible (without interfering with your work).

User Website Directory

Users interested in sharing files publicly via the World Wide Web can request a user website directory be created for their account. User website directories (~/www) have a 5GB storage quota and allow access to files at http://users.nccs.gov/~user (where user is your userid). If you are interested in having a user website directory created, please contact the User Assistance Center at help@olcf.ornl.gov.

User Archive Directories (HPSS)

The High Performance Storage System (HPSS) at the OLCF provides longer-term storage for the large amounts of data created on the OLCF compute systems. The mass storage facility consists of tape and disk storage components, servers, and the HPSS software. After data is uploaded, it persists on disk for some period of time. The length of its life on disk is determined by how full the disk caches become. When data is migrated to tape, it is done so in a first-in, first-out fashion.

User archive areas on HPSS are intended for storage of data not immediately needed in either User Home directories (NFS) or User Work directories (GPFS). User Archive directories should not be used to store project-related data. Rather, Project Archive directories should be used for project data.

User archive directories are located at /home/$USER.

User Archive Access

Each OLCF user receives an HPSS account automatically. Users can transfer data to HPSS from any OLCF system using the HSI or HTAR utilities. For more information on using HSI or HTAR, see the HPSS Data Archival System .

User Archive Accounting

Each file and directory on HPSS is associated with an HPSS storage allocation. For information on HPSS storage allocations, please visit the Policy section.

For information on usage and best practices for HPSS, please see the HPSS Data Archival System documentation.