Linux中的du命令也是查看使用空间的，与df命令不同的是，Linux du命令是对文件和目录磁盘使用的空间的查看，所以它和df命令还是有一些区别的。
1．命令格式
du [选项][文件]
2．命令功能
显示每个文件和目录的磁盘使用空间。
3．命令参数
-a或-all显示目录中个别文件的大小。-b或-bytes显示目录或文件大小时，以byte为单位。-c或--total除了显示个别目录或文件的大小外，同时也显示所有目录或文件的总和。-k或--kilobytes以KB(1024bytes)为单位输出。-m或--megabytes以MB为单位输出。-s或--summarize仅显示总计，只列出最后加总的值。-h或--human-readable以K，M，G为单位，提高信息的可读性。-x或--one-file-xystem以一开始处理时的文件系统为准，若遇上其它不同的文件系统目录则略过。-L<符号链接>或--dereference<符号链接> 显示选项中所指定符号链接的源文件大小。-S或--separate-dirs显示个别目录的大小时，并不含其子目录的大小。-X<文件>或--exclude-from=<文件> 在<文件>指定目录或文件。--exclude=<目录或文件> 略过指定的目录或文件。-D或--dereference-args显示指定符号链接的源文件大小。-H或--si与-h参数相同，但是K，M，G是以1000为换算单位。-l或--count-links重复计算硬件链接的文件。
4．使用实例
实例1：显示目录或者文件所占空间
命令：
du
输出：
[zaixian@localhost ~]$ du
24 ./test4
0 ./project/lib
0 ./project/bin
0 ./project/doc/info
0 ./project/doc/product
0 ./project/doc
0 ./project/logs/info
0 ./project/logs/product
0 ./project/logs
0 ./project/service/deploy/info
0 ./project/service/deploy/product
0 ./project/service/deploy
0 ./project/service
0 ./project
4 ./logs/test3
4 ./logs
4 ./scripts
84 .
[zaixian@localhost ~]$
说明：
只显示当前目录下面的子目录的目录大小和当前目录的总的大小，最下面的1288为当前目录的总大小
实例2：显示指定文件所占空间
命令：
du log3.log
输出：
[zaixian@localhost ~]$ du log3.log
560 log3.log
[zaixian@localhost ~]$
实例3：查看指定目录的所占空间
命令：
du /usr/local
输出：
[zaixian@localhost ~]$ du /usr/local/
0 /usr/local/bin
0 /usr/local/etc
0 /usr/local/games
0 /usr/local/include
0 /usr/local/lib
0 /usr/local/lib64
0 /usr/local/libexec
0 /usr/local/sbin
0 /usr/local/share/applications
0 /usr/local/share/info
0 /usr/local/share/man/man1
0 /usr/local/share/man/man1x
0 /usr/local/share/man/man2
0 /usr/local/share/man/man2x
0 /usr/local/share/man/man3
0 /usr/local/share/man/man3x
0 /usr/local/share/man/man4
0 /usr/local/share/man/man4x
0 /usr/local/share/man/man5
0 /usr/local/share/man/man5x
0 /usr/local/share/man/man6
0 /usr/local/share/man/man6x
0 /usr/local/share/man/man7
0 /usr/local/share/man/man7x
0 /usr/local/share/man/man8
0 /usr/local/share/man/man8x
0 /usr/local/share/man/man9
0 /usr/local/share/man/man9x
0 /usr/local/share/man/mann
0 /usr/local/share/man
0 /usr/local/share
163804 /usr/local/src
163804 /usr/local/
[zaixian@localhost ~]$
实例4：显示多个文件所占空间
命令：
du file1 file2
输出：
[zaixian@localhost test4]$ du log.tar log3.log
12 log.tar
448 log3.log
[zaixian@localhost test4]$
实例5：只显示总和的大小
命令：
du -s
输出：
[zaixian@localhost ~]$ du -s
1084 .
[zaixian@localhost ~]$ du -s project/
0 project/
[zaixian@localhost ~]$ du -s test4/
468 test4/
[zaixian@localhost ~]$
实例6：方便阅读的格式显示
命令：
du -h dir
输出：
[zaixian@localhost ~]$ du -h project/
0 project/lib
0 project/bin
0 project/doc/info
0 project/doc/product
40K project/doc
0 project/logs/info
0 project/logs/product
152K project/logs
0 project/service/deploy/info
0 project/service/deploy/product
0 project/service/deploy
0 project/service
192K project/
[zaixian@localhost ~]$
实例7：文件和目录都显示
命令执行和输出：
[zaixian@localhost ~]$ du -ah project/
0 project/lib
0 project/bin/run.py
0 project/bin
0 project/doc/info
0 project/doc/product
40K project/doc/test.txt
40K project/doc
0 project/logs/info
0 project/logs/product
148K project/logs/readme.txt
4.0K project/logs/log201710.log
152K project/logs
0 project/service/deploy/info
0 project/service/deploy/product
0 project/service/deploy
0 project/service
192K project/
[zaixian@localhost ~]$
实例8：显示几个文件或目录各自占用磁盘空间的大小，还统计它们的总和
命令：
du -c log3.log log1.log text.txt
输出：
[zaixian@localhost ~]$ ll
total 572
-rwxr-xr-x. 1 zaixian zaixian 464 Feb 15 20:58 log1.log
-rw-rw-r--. 1 zaixian zaixian 0 Feb 15 20:43 log2018.log
-rw-rw-r--. 1 zaixian zaixian 0 Feb 15 20:43 log2019.log
-rw-rw-r--. 1 zaixian zaixian 0 Feb 15 20:43 log2020.log
-rwxrwxr-x. 1 zaixian zaixian 0 Feb 15 20:43 log2.log
-rw-rw-r--. 1 zaixian zaixian 571759 Feb 17 04:02 log3.log
lrwxrwxrwx. 1 zaixian zaixian 7 Feb 15 22:46 log_link.log -> log.log
-rwxr-xr-x. 1 zaixian zaixian 0 Feb 16 21:38 log.log
drwxrwxr-x. 3 zaixian zaixian 35 Feb 16 20:54 logs
drwxrwxr-x. 7 zaixian zaixian 66 Feb 15 20:48 project
-rw-rw-r--. 1 zaixian zaixian 0 Feb 17 02:01 run.py
drwxrwxr-x. 2 root zaixian 67 Feb 17 02:38 scripts
-rw-rw-r--. 1 zaixian zaixian 0 Feb 15 21:10 test3.log
drwxrwxr-x. 2 zaixian zaixian 177 Feb 16 21:28 test4
-rw-rw-r--. 1 zaixian zaixian 19 Feb 15 21:08 text.txt
-rw-rw-r--. 1 zaixian zaixian 1 Feb 15 20:46 tmpcore.log
[zaixian@localhost ~]$ du -c log3.log log1.log text.txt
560 log3.log
4 log1.log
4 text.txt
568 total
[zaixian@localhost ~]$
说明：
加上-c选项后，du不仅显示两个目录各自占用磁盘空间的大小，还在最后一行统计它们的总和。
实例9：按照空间大小排序
命令：
du|sort -nr|more
输出：
[zaixian@localhost ~]$ du|sort -nr|more
1276 .
468 ./test4
192 ./project
152 ./project/logs
40 ./project/doc
4 ./scripts
4 ./logs/test3
4 ./logs
0 ./project/service/deploy/product
0 ./project/service/deploy/info
0 ./project/service/deploy
0 ./project/service
0 ./project/logs/product
0 ./project/logs/info
0 ./project/lib
0 ./project/doc/product
0 ./project/doc/info
0 ./project/bin
[zaixian@localhost ~]$
实例10：输出当前目录下各个子目录所使用的空间
命令：
du -h --max-depth=1
输出：
[zaixian@localhost ~]$ ll
total 572
-rwxr-xr-x. 1 zaixian zaixian 464 Feb 15 20:58 log1.log
-rw-rw-r--. 1 zaixian zaixian 0 Feb 15 20:43 log2018.log
-rw-rw-r--. 1 zaixian zaixian 0 Feb 15 20:43 log2019.log
-rw-rw-r--. 1 zaixian zaixian 0 Feb 15 20:43 log2020.log
-rwxrwxr-x. 1 zaixian zaixian 0 Feb 15 20:43 log2.log
-rw-rw-r--. 1 zaixian zaixian 571759 Feb 17 04:02 log3.log
lrwxrwxrwx. 1 zaixian zaixian 7 Feb 15 22:46 log_link.log -> log.log
-rwxr-xr-x. 1 zaixian zaixian 0 Feb 17 04:16 log.log
drwxrwxr-x. 3 zaixian zaixian 35 Feb 16 20:54 logs
drwxrwxr-x. 7 zaixian zaixian 66 Feb 15 20:48 project
-rw-rw-r--. 1 zaixian zaixian 0 Feb 17 02:01 run.py
drwxrwxr-x. 2 root zaixian 67 Feb 17 02:38 scripts
-rw-rw-r--. 1 zaixian zaixian 0 Feb 15 21:10 test3.log
drwxrwxr-x. 2 zaixian zaixian 177 Feb 16 21:28 test4
-rw-rw-r--. 1 zaixian zaixian 19 Feb 15 21:08 text.txt
-rw-rw-r--. 1 zaixian zaixian 1 Feb 15 20:46 tmpcore.log
[zaixian@localhost ~]$ du -h --max-depth=1
468K ./test4
192K ./project
4.0K ./logs
4.0K ./scripts
1.3M .
[zaixian@localhost ~]$