# Quotas and Purging¶

## Overview¶

Directory Default space quota Default inode quota Purge time
$HOME 500 GB 1 M - $SCRATCH 10 TB 1 M 60 days
/work/projects/... 16 MB 0 -
/mnt/isilon/projects/... 1.14 PB globally - -

## Quotas¶

Warning

When a quota is reached writes to that directory will fail.

Note

On Isilon everyone shares one global quota. Unfortunately it is not possible to see the quota status on the cluster.

### Current usage¶

We provide the df-ulhpc command on the cluster login nodes, which displays current usage, soft quota, hard quota and grace period. Any directories that have exceeded the quota will be highlighted in red.

Once you reach the soft quota you can still write data until the grace period expires (7 days) or you reach the hard quota. After you reach the end of the grace period or the hard quota, you have to reduce your usage to below the soft quota to be able to write data again.

Check current space quota status:

df-ulhpc


Check current inode quota status:

df-ulhpc -i


Check free space on all file systems:

df -h


Check free space on current file system:

df -h .


### Increases¶

If you or your project needs additional space or inodes for your scratch or project directory you may request it via ServiceNow (HPC → Storage & projects → Extend quota).

Quotas on the home directory cannot be increased.

### Troubleshooting¶

The quotas on project directories are based on the group. Be aware that the quota for the default user group clusterusers is 0. If you get a quota error, but df-ulhpc and df-ulhpc -i confirm that the quota is not expired, you are most likely trying to write a file with the group clusterusers instead of the project group.

To avoid this issue, check out the newgrp command or set the s mode bit ("set group ID") on the directory with chmod g+s <directory>. The s bit means that any file or folder created below will inherit the group.

To transfer data with rsync into a project directory, please check the data transfer documentation.

## Purging¶

Files in the scratch (\$SCRATCH, /mnt/lscratch) directories are purged. This means files that have not been read (i.e. atime has not been updated) within the last 60 days are automatically removed every month.

Files in /tmp on the compute nodes are removed at the end of the job.

Last update: January 20, 2021