In order to reconcile the large number of students and the limited space of the hard disks, there is a space restriction for users with RBG/ISP accounts called quota. This is usually 1Gbyte.

Most of the time you will be confronted with the quota if a program reacts “abnormal”, e.g. if doesn't start correctly or the graphical user interface is reacting very slowly especially during the login. This is connected to the fact that the program is unable to create temporary files and stop its service abruptly.

The problem are mainly the hidden files and folders. To get to the bottom of this, you should use the command tell-me-disk-usage in the shell/in the terminal. This command will show you the programs which use the most space.

To get the information of the currently used space, you should use the command quota -v. Without the parameter you might only get a warning from the hard drives where the quota is stored.

• The output of the program can be interpreted in different ways:
  • the filesystem shows the each hard drive.
  • the quota is a limitation, but there is a warning. Please don't reach this limitation!
  • the limit is the absolut limitation! There is no more space at all.

The command du -h (disk usage, output comes in the matching size) shows you all information about the directory and the files inside. The output can be piped using xdu, which shows the outcome graphical, e.g. for the home-directory:

du -h ~/ | sort -nr | xdu

The command sort -nr ensures that the entries are sorted by size: the “main problem” (the biggest file or folder) will be standing right in front.

You can also get the output colorful: qdu scans the current directory and creates an overview, where the programs and files which use the most space are standing right in front. For an informative overview you should click on the third button on the right (“show hidden files”).

• as alternative you can use the command:

tell-me-disk-usage

It will show you the folders which use the most space.

Another very comfortable alternative is the graphical program “filelight” which is installed on the pool-computers. The fastest way to start the program is the keyboard combination “AlT + F2” and after that write “filelight” (without quotation marks). After the start you can chose “Heimat Verzeichnis einlesen”. After a little while a graphical interface shows up and you can see the use of the hard drive.

The common suspects are on the one hand .mozilla (Mozilla/Firefox/SeaMonkey-profiles, contain cache-directories) and on the other hand .adobe (Acrobat-Font-caches, for each computer one…).

Furthermore another program which uses a lot of space is Ecplipse with its plugins. More common as a reason is the folder ~/.m2.

First of all you should really try to avoid to get over the quota. If this happens anyway you can check the following points in order:

1. core-files can be deleted without scruples. They are created when a program fails and have debugging purposes.

An easy way to find such files is using the command ~ -name core

1. Sometimes the cache of Mozilla/Firefox/SeaMonkey is too big. To solve this problem you can downsize the cache or delete, because most of the information in the cache aren't that important. To do so, you can use the command: rm -rf ~/.mozilla/*/*/Cache/*.
2. The Acrobat Reader creates a font-cache-file in .adobe on every computer when you start the program (and these are all ultras depending on the user behaviour). These files can be read using the command ls -la ~/.adobe and can be deleted without scruples. An eventually existing subdirectory Acrobat often also contains a cash, which can be delete using the command rm -rf ~/.adobe/Acrobat/9.0/Cache.
3. Big files that you don't need anymore, can also be deleted. You have to know by yourself which files you don't need anymore. The command ls -ls | sort -n lists the files of one directory in ascending order by size.
4. If nothing of this work (and only than!) you can ask the RBG/ISP for help.