Due to the unfortunate fact that resources are limited, each student has a fixed amount of disk space available -- a disk quota. Undergraduate students are generally allocated fifty megabytes (50MB) plus twenty megabytes (20MB) per course. This should be sufficient for all of your coursework. Some courses allow you more space because they involve the use of particularly large files. You can check your quota using the rquota command, which produces an output along the lines of:
blocks quota limit #warns files quota limit #warns 3496 5048 10096 169 10480 21480
`blocks' is the amount of disk space you are currently using, `quota' is the amount you are allowed indefinitely (`soft block limit') and `limit' is the absolute maximum you can use (`hard block limit'). When you exceed your soft limit you will receive a warning email informing you of how much time you have to reduce your usage before your soft block limit is enforced. When this limit is enforced you will not be able to create any more files, receive email or, in fact, do much except delete or compress files to reduce the amount of space you are using. When you exceed your quota you have approximately one week to get it back under control.
Similar to the disk space quota is the quota on the number of files you may have. This is shown in the second half of the rquota output and works in much the same way as the disk space quota. In both cases `#warns' is the number of days left before the soft limit is enforced.
It is extremely easy to fill up disk space and exceed your quota without realising it. Any file automatically generated by the computer can quickly grow very large, as can graphics files (especially in postscript or bitmap formats). Copious amounts of email, or very large email messages and/or attatchments will quickly eat up space while they sit in your mailbox. Web downloads, particularly images and sound, should be treated with extreme caution.
You can get more detailed information by using the disk_guess command which will list your six biggest files and six biggest directories. If you run disk_guess -p, you will also get a listing of recent file size changes.
Running disk_guess will produce an output similar to:
You are currently using 2264K which is below your quota of 10240K Your 6 biggest files are: 208K ( 9.19%) in ./.netscape/cert7.db 148K ( 6.54%) in ./.netscape/cache/1C/cache3B14957C003044B.pdf 48K ( 2.12%) in ./.incoming-mail 40K ( 1.77%) in ./.netscape/history.db 36K ( 1.59%) in ./Library/TEX/SimpleLibrary.mch.prf.0.dvi 32K ( 1.41%) in ./.netscape/cert5.db Your 6 biggest directories are: 592K (26.15%) in ./.netscape 380K (16.78%) in ./GNUstep 336K (14.84%) in ./GNUstep/Library 328K (14.49%) in ./GNUstep/Library/WindowMaker 288K (12.72%) in ./JavaFiles 244K (10.78%) in ./Library You have 732K used up in dot files (or directories) larger than 20K. The dot files are: 92K in ./.kde 592K in ./.netscape 48K in ./.incoming-mail You have 200K (8.8%) used in netscape cache files. These are almost certainly unnecessary. To remove them, run rm -r .netscape/cache/*
core files are another easy way to consume disk space. When a program crashes, it will often `dump core', creating a core file containing information about the state of the program when it crashed. core files are often very large (megabytes), but are also very useful when trying to work out what went wrong. If you don't intend to use them for this purpose, they can be safely deleted by using the rm command.
% rm coreLoc Van Huynh 2007-03-15