Information for Principal Investigators

All Tetralith and Sigma disk storage¹ is connected to a project².

As the Principal Investigator (PI) of a project, you are responsible for providing enough storage to your project members, and to decide how files and directories should be stored within the project directory.

The day-to-day work of organizing data, discussing storage needs with NSC does not necessarily have to be done by the PI. Please contact NSC Support if you want to delegate these tasks to someone else within your project.

What PIs should do to manage their project’s storage

• Keep track of and manage your project’s disk usage. A command-line tool (e.g storagequota -a) is available that you can run on the cluster to see who is using how much of your project’s disk space. A notification system is in place that will email you when the project storage quota is exceeded (the emails can also be sent to all project members or a list of addresses if you prefer that). You can see the project’s disk usage over time in SUPR.
• Apply for more storage space when needed. See this page for more information on this.
• Plan for what to do with your project’s data when the project ends. If you’re granted a new project that will continue using the same data, you can choose to keep your old project storage directory. A storage directory that is no longer connected to an active project becomes read-only after 30 days, and is deleted permanently after another 60 days!

How much data can be stored in your project directory? (quota)

• The total volume of data that can be stored in your project directory is limited.
• The limit/allocation is different for each project.
• New projects are given a default allocation of 500 GiB. If you need more than that, please read this page for information on how to apply for more space.
• Do not hesitate to apply for more space if that is needed to work efficiently in your project! The default allocation (500 GiB) is intentionally set fairly low. Most projects with many members or handling large data sets will need to apply for more space.
• There is also a limit of how many files can be stored (because storing many small files has a greater “cost” in terms of system performance than storing few large files). If you need to store more files than the default limit of one million files per project, please contact NSC Support.

Limiting how much data each user can store

Most projects seems to get along fine without limiting how much each user can store inside the project directory.

However, it is possible for one user to fill up the entire project storage directory and cause problems (e.g failed jobs) for other users.

If you find that you need more control over who gets to use how much storage space, we can place limits on individual users or groups of users within a certain project directory. If you’re interested in using such limits, please contact NSC Support.

Who can store data in the project directory?

By default, only members of your project will be able to read and write files in the project directory. It is possible to allow others to e.g read files from the project directory or parts of it. Please contact NSC Support if you want to open up your project directory to non-members.

When a project directory is taken over by a new project, the members of the old project can access the directory for a period of 60 days after the old project ends.

Ownership of data and the rights to use project storage

NSC’s position is that computing time and project storage are allocated to the project by NAISS, and that NAISS has authorized the PI to decide who gets to be a member in the project, and how much computing and storage resources each member may use.

In order to manage the project storage, the project PI (or someone designated by the PI) can therefore get assistance from NSC with the following:

• See how much storage space is used by each project member.
• Read the contents of any directories/files within the project storage directory (e.g to determine what type of data is stored if it should be kept).
• Delete any data within the project storage directory (e.g to free up space used by unwanted files owned by inactive users).
• Change ownership and file permissions of any data within the project directory (e.g to take ownership of still-relevant files from inactive users).

We strongly encourage PI:s to talk to project members before deleting or changing the ownership of their data.

Please note that NSC considers this to be unrelated to the intellectual property rights of the actual file contents. This just concerns the rights to store and organize bits and bytes on disk.

When a user is removed from a project, files in the project directory owned by that user are not automatically removed. It is up to the project PI to decide if the files should be kept on disk or not.

A user’s home directory is considered to be personal and not connected to any project. NSC will not allow PI:s to delete or view contents from the home directory without permission from the user. Home directories of users no longer active at NSC will eventually be deleted.

Renaming a storage directory

Renaming an existing storage directory (e.g /proj/foo to /proj/bar) is not possible.

Several technical details combined makes this just too inconvenient for users and time-consuming for NSC staff that we have decided to not allow it.

If your directory name is no longer relevant, e.g due to organizational changes, we recommend that you choose a new directory name for your next project. You will then have 60 days in which to move the data you want to keep from the old to the new directory.

If you require assistance in moving the data from the old directory to the new one, contact NSC Support.