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Project File System

Overview

The project file system is a global file system available to all NERSC computational systems. It allows groups of NERSC users to store and share data. A directory in the project file system is available by default for each repository.

Purging

No, files in Project are not subject to purging. 

Backup

Daily backups are performed for project directories whose quotas are equal to or less than 5 TB; such backups are kept for 90 days.

If you require a restoration of lost data, please contact NERSC Consulting with pathnames and timestamps of the missing data. Such restore requests may take a few days to complete,  restore time being dependent on the amount of data being retrieved. No backups are performed on project directories whose quotas are greater than 5 TB. IMPORTANT: All NERSC users should back up important files to HPSS on a regular basis.  Ultimately, it is your responsiblity to protect from data loss.

Access Control

There must be a project directory administrator associated with each project directory. This user must have a NIM role of PI, PI Proxy, or Project Manager.

Access control for project directories is based on Unix file groups. In most situations, the name of the project directory is the same as the associated file group.

Quotas

Default project directory quotas are 1 TB and 1,000,000 inodes. If your directory needs more than that, fill out the Disk Quota Increase Form.

To check your current usage and quota in a project directory, use the prjquota command, specifying the name of the project directory. For example, if you have access to a project directory named "bigsci":

% prjquota bigsci
------ Space (GB) ------- ----------- Inode -----------
Project Usage Quota InDoubt Usage Quota InDoubt
-------- ------- ------- ------- ------- ------- -------
bigsci 1455 3072 0 307423 500000 20

In the above example, the project directory "bigsci" has used about 1.5 TB of its 3 TB block quota, and about 307000 inodes out of its 500000 inode quota.

Performance

The system has a peak aggregate bandwidth of 40 GB/sec bandwidth for streaming I/O, although actual performance for user applications will depend on a variety of factors. Because NGF is a distributed network filesystem, performance typically will be less than that of filesystems that are local to a specific compute platform. This is usually an issue only for applications whose overall performance is sensitive to I/O performance.

Usage

Project directories are created in /project/projectdirs. The name of the project directory is the same as the associated Unix file group. This name will be the same as a NERSC repository, and all active users of that repository (which is already a Unix file group) will thereby have access to the project directory.

Occasionally there are cases where an additional project directory may be required. For example, some large projects might want a project directory to be accessible by members of multiple repositories. Also, some long-term projects outlive the specific repositories that constitute them. In these cases, a project directory administrator may request the creation of a "designer" project name. This will result in the creation of a new Unix file group consisting soley of the project directory administrator, followed by the creation of the project directory itself. The project directory administrator must then use NIM to add users to the newly-created file group (this is a very simple operation). Only these users will be able to access the project directory. To request a designer project directory, please use the Project Directory Request Form.