sudo du -h --max-depth 1 /
14M	/etc
du: cannot access ‘/run/user/1000/gvfs’: Permission denied
1.7M	/run
du: cannot access ‘/proc/3777/task/3777/fd/4’: No such file or directory
du: cannot access ‘/proc/3777/task/3777/fdinfo/4’: No such file or directory
du: cannot access ‘/proc/3777/fd/4’: No such file or directory
du: cannot access ‘/proc/3777/fdinfo/4’: No such file or directory
0	/proc
152M	/opt
8.0K	/media
125M	/boot
12M	/sbin
40K	/root
148K	/tmp
9.7M	/bin
8.0K	/dev
4.1G	/usr
3.5M	/lib32
16K	/lost+found
4.0K	/cdrom
4.0K	/mnt
4.0K	/lib64
4.0K	/srv
968M	/lib
660M	/var
13G	/home
0	/sys
19G	/