Identifying Accounts That Use Large Amounts of Disk Space

Identifying Accounts That Use Large Amounts of Disk Space

Four commands are useful for tracking down accounts that use large amounts of space: du, find, quot, and diskusg.

du displays disk use, in blocks, for files and directories. For example:

# du /usr/share/catman/u_man 
5       /usr/share/catman/u_man/cat1/audio
266     /usr/share/catman/u_man/cat1/Xm
1956    /usr/share/catman/u_man/cat1/X11
72      /usr/share/catman/u_man/cat1/Inventor
413     /usr/share/catman/u_man/cat1/dmedia
752     /usr/share/catman/u_man/cat1/explorer
12714   /usr/share/catman/u_man/cat1
1       /usr/share/catman/u_man/cat3/audio
63      /usr/share/catman/u_man/cat3
12      /usr/share/catman/u_man/cat6/video
1077    /usr/share/catman/u_man/cat6
92      /usr/share/catman/u_man/cat2
425     /usr/share/catman/u_man/cat4
170     /usr/share/catman/u_man/cat5
13      /usr/share/catman/u_man/cat1m
14557   /usr/share/catman/u_man

This displays the block count for all directories in the directory /usr/share/catman/u_man. By default the du command displays disk use in 512-byte blocks. To display disk use in 1024-byte blocks, use the -k option. For example:

# du -k /usr/people/ralph

The -s option produces a summary of the disk use in a particular directory. For example:

# du -s /usr/people/alice

For a complete description of du and its options, see the du(1M) reference page.

Use find to locate specific files that exceed a given size limit. For example:

# find /usr -local -size +10000 -print

This example produces a display of the pathnames of all files (and directories) in the Usr filesystem that are larger than 10,000 512-byte blocks.

The quot command reports the amount of disk usage per user on an EFS filesystem. It is part of the disk quotas subsystem, although you need not use quotas to use this command. You can use the output of this command to inform your users of their disk space usage. An example of the command is:

# /usr/etc/quot /
/dev/root (/):
  371179    root    
  265712    ellis   
   12606    aevans  
    7927    demos   
    5526    bin     
    2744    lp      
     682    uucp    
     379    guest   
     207    adm     
       7    sys

The diskusg command is part of the process accounting subsystem and serves the same purpose as quot. diskusg, though, is typically used as part of general system accounting and can be used on both EFS and XFS filesystems. This command generates disk usage information on a per-user basis. For example,

# /usr/lib/acct/diskusg /dev/root 
0       root    736795
2       bin     11035
3       uucp    1342
4       sys     9
5       adm     1011
9       lp      5418
126     ellis   528263
993     demos   15737
998     guest   740
5315    aevans  24836

diskusg prints one line for each user identified in the /etc/passwd file. Each line contains the user's UID number and login name, and the total number of 512-byte blocks of disk space currently being used by the account.

The output of diskusg is normally the input to acctdisk (see the acct(1M) reference page), which generates total disk accounting records that can be merged with other accounting records. For more information on the accounting subsystem, consult the guide IRIX Admin: Backup, Security, and Accounting and the acct(4) reference page.