Overview of available file systems

File system + mount point

Environment Variable for Access

PurposeType and SizeBackup and snapshotsIntended lifetimeCleanup strategy QuotaAvailable for

/home

$HOME

Store source files, input data, small files

Globally accessible from login and compute nodes

GPFS, 100TB

backup to disks and snapshots

Account lifetimeNo cleanup

100GB

per user

All users

/work

$WORK 

Collaboration space for a group
Common software, result files and data sets

Globally accessible from login and compute nodes

GPFS, 100TB

Backup upon request, at cost price.

Snapshots

Group lifetimeNo cleanup

50GB*

per group

All EPFL units (upon request).
Not available for bachelor/master students.

/scratch

$SCRATCH 

Temporary huge result files

Accessible from the frontend and compute nodes within one cluster.

Fidis:
GPFS, 375TB

Helvetios:
GPFS, 186TB

Izar:
GPFS, 253TB

No backup, no snapshots

2 weeks


Automatic deletion of files and empty directories older than two weeks may happen without noticeQuotas may be in place to prevent runaway tasks filling the filesystem. A typical limit would be 1/3 or 1/2 of the total space.All users

/tmp/${SLURM_JOB_ID}

$TMPDIR

Temporary, local file space for jobs on compute nodes.

Not available on login nodes.

local (node), between 64 and 512 GB

No backup, no snapshots

Job execution


Content is deleted after job endnoAll users

* Space on work is charged for and, as such, the quota of the group depends on the amount of space purchased.  There is no backup by default but a laboratory may request such a service. The price for backup will be the cost price to SCITAS.

/work storage creation requests

The price for work is per TB/year, usually sold for 3 years, and can be found in our website:
https://www.epfl.ch/research/facilities/scitas/getting-started/prospective-users-howto/

Each group can have 50GB for free.

Security of user data

The contents of the home file-system are backed-up on a daily basis with a six month retention period. The backed up data are held at a separate physical location to the original data.

The contents of the work file-system are not backed up by default

The scratch file-systems are not backed-up under any circumstances.

The scratch file-systems are only for short-lived files and, in the case of insufficient free space, files older than two weeks may be deleted without notice in order to ensure the usability of the cluster.


Scratch automatic cleanup

When a scratch filesystem reaches a certain level of use (normally 90%) an automatic cleanup procedure is activated. Starting with the oldest files present deletion takes place until the occupancy has been reduced to 70%. Only files less than 2 weeks old are sure not to be deleted by the cleanup mechanism.



Files belonging to a former user

When a user no longer has a valid account on the clusters any files belonging to him on home are removed from the servers. They will remain on backup for 6 months after the user has left EPFL. The head of the laboratory is responsible for ensuring that these data are correctly managed. He or she can ask for a retrieval from backup.

The work file-system is divided by laboratory and, as directories of users who leave EPFL cannot be deleted by their colleagues, an intervention is required.
Any "professional data" of users who leave EPFL should be passed on to "a person designated by the head of the unit" (translated from LEX 6.1.4, Article 25]).
Please contact us to
change the ownership of any files/folders to a person designated by the responsible of the group that can assess the value of the data and handle it accordingly (delete or archive).

Once a user is no longer accredited, files belonging to them in scratch can be deleted without notice.


How to recover snapshots

A snapshot is the state of a system at a particular point in time. On our clusters, the home and work filesystems are snapshotted daily and snapshots are kept for one week. This is particularly useful in case a user removes a file by mistake.

Daily snapshots of the home and work filesystems can be found in /home/.snapshots, /work/.snapshots, respectively.