Disk Quotas

You have a /home/username directory and a /work/username directory. This disk space has quotas imposed on it to prevent us running out of disk space.

The default quota for home directories is 5 GB and for work directories it is 50 GB. This is known as the soft limit. You can exceed this soft limit for up to 1 week up to something called the hard limit (6 GB for home and 60GB for work) during which time you will receive filesystem warnings on the screen ... after this time your account will lock-up. You may have the quota increased on your work directory, but not your home directory.

Your home directory is where you should keep your mail folders, web pages, papers and codes. Your work directory is where you should keep your data, as this is reproducible, or items you won't need for long, or that don't change frequently.

If you have significant quantities of data that doesn't need backing up, ask the computing staff for a /data directory.

The reason we have both /home and /work directories has to do with performance and also backups. Interactive performance is maximized for home directories on our system because it is spread across a large number of disks on our fileserver which can all provide information to users simultaneously. Also, Home directory backups are kept for a longer time (2 years vs 3 months on /work), so we need to limit their size. Home directories also have a feature called snapshots which are like an online backup. See this page to learn more.

Determining Your Quotas and Usage

To find out your disk and file quotas, execute the following commands:

ls /work/username
quota -sv

An example output for user 'test' is as follows:

Disk quotas for user test (uid 123): 
     Filesystem  blocks   quota   limit   grace   files   quota   limit   grace
pegasus:/vol/vol0/home/test
                  1320M   2048M   2500M           14656    134k    154k        
dionysus:/vol/vol1/work/test
                     28  51200M  61440M               6   4295m   4295m