How to check your file quota

There is a limit on the amount of disk space on the fileservers which students and staff are allowed to use. This is known as disk quota and (from October 2015) is set at 8GB and 40,000 files for everyone in DoC. Of course CSG can increase a user's quota where necessary, this is discussed further right at the end of this guide.

This quota covers any files and sub-directories created in your home directory. Your home directory is your initial working space when you log in to any DoC Linux system, and is the H: drive on DoC Windows systems.

Your disk quota actually comprises four separate limits, two on space and two on number of files. For each quantity (space and files) there are two limits - a soft limit ("quota") and a hard limit ("limit"). Currently these are:

space quota


space limit


files quota


files limit


This allows you to store up to 8GB at all times, and allows you to store between 8GB and 8.1GB for up to 7 days at a time. Similarly, it allows to store up to 40,000 files at all times, and between 40,000 and 41,000 files for up to 7 days.

Checking your quota and disk space used

We recommend that you check your quota (showing how much disk space, and how many files, you are using) a couple of times a week by typing:

quota -Q

on the shell command line of any DoC Linux system. The only way to check your quota when running Windows is to log in to a Linux host via an ssh client (eg. putty) and run the quota command as above.

The output will be similar to:

Disk quotas for user zzzz10 (uid 9999):
     Filesystem  blocks    quota   limit   grace   files   quota   limit   grace
                  22400  8000000 8100000            1800   40000   41000

This shows you the various file spaces on which you have a quota. In this example, your home directory is held on a filesystem called /export on the file server redkite, you're using 22MB (megabytes) of disk space at present, with a quota of 8GB and a hard limit of 8.1GB (8100MB). You have 1800 files, and a file quota of 40K files, 41K in total. On a busy machine (eg. a shell server) you might even see your own quota several times in a confusing fashion; just ignore all but one.

What happens when I go over my quota?

When you exceed your quota, the above quota report will show a timer that starts counting down to zero (in one of the "grace" columns), and you must delete enough files to come back under quota before the counter expires.

If you either hit your hard limit, or allow the over-quota timer to expire (i.e. leave yourself over quota for a whole week) the consequences will be:

How can I reduce my usage once I have reached my hard limit?

If you reached the total amount of disk space you are allowed to use you will not be able to log in via X-windows (KDE/Gnome). This is because the system creates a temporary file in your account when you log in. If there is no space to do so, you can't log in. You can log in if you avoid X-windows.

On Linux workstations type Ctrl-Alt-F1 to get a text-mode login prompt. Log in, find where you're using the space (using the commands from the following sections), then clear some space by removing or compressing files until your quota comes under the soft limit, using the command quota -Q to check periodically). Then log out of the text-mode login, and then press Ctrl-Alt-F8 to return the machine to X-Windows, and login in graphically.

You can also clear space by logging in via Windows and either removing files from the H: drive or ssh'ing into a shell server. Take care not to remove any important Linux setup files!

Where am I using all the space?

People often think they are only using say 200MB of space and when quota reports they are using 8GB they don't believe it! The truth is that many applications you use store data in files you don't even realise are there. KDE, Gnome, web browsers and miscellaneous junk like pulseaudio are notorious for storing stuff behind the scenes. Make sure you empty your Gnome or KDE trashcan, and clear up all the junk on your desktop for a start! The following commands will show which directories or files are taking up most space in the top-level of your home directory.


The largest files or directories will appear at the end of the list. The usage command is a short shell script that essentially runs du | sort. du can summarise disk usage in various ways - see the manual page (type man du) for other options.

You might want to add that command to the end of your .cshrc file as an alias:

alias usage '/vol/linux/bin/usage'

then on future logins (or immediately, after running source ~/.cshrc) you can simply type:


When you found a suspicuously large directory, you can repeat the process one level down (and so on):


until you find a flat directory containing an unexpectedly large amount of space - then you might consider deleting some of the contents (once you understand what it is, of course).

Where am I using all the files?

Checking which directories contain the most number of files is slightly trickier. For a single directory such as ~/public_html, the command:

find ~/public_html | wc -l

will show the total number of files and directories [both of which count towards your file limits] within that directory.

So, in order to do that for all sub-directories in your current directory, producing the output in sorted order, one needs to write a short script. Fortunately, we have already written one for you, so just run:


This produces a list of sub-directories [under the current directory] sorted by number of files contained. The directories with the largest number of files appear at the bottom of the list.

As with usage, you may want to use nfiles to drill down, as in:


When you find a directory with a suspicuously large number of files in it, you can repeat the process one level down (and so on):


until you find a flat directory containing an unexpectedly large number of files - then you might consider deleting some of those files (once you understand what the directory and it's files are, of course).

Making the most of your quota

There are several recommended methods for getting the most out of your file space.

Edit -> Preferences -> Advanced -> Network

limit coredumpsize 0

tar czvf <filename.tgz> <list of files to archive>

Other storage areas

Getting your quota extended

The disk space quota is set by discussion with the academic staff, in particular with Peter McBrien, the Director of UG Studies. Your quota is considered adequate for most academic work and you would need a good reason to be allocated any more (eg. final year project work involving video streams or coursework involving a 10,000 file git repository:-)). You're welcome to email and explain how much more quota (space or files) you think you need, why, and for how long. We'll discuss it with you and decide whether it's a reasonable request.

See Also:

We've just started creating a series of short guides, PDF documents ready to print:

guides/file-storage/quota (last edited 2015-10-05 15:11:25 by dcw)