Can't figure out how I should clean up my rootfs partition. It's 95% used, with total of 9.1G in space. Isn't that much for a root partition? This is my ouput of df -h command:    /# df -hFilesystem                                              Size  Used Avail Use% Mounted onrootfs                                                  9.1G  8.2G  471M  95% /udev                                                     10M     0   10M   0% /devtmpfs                                                   1.6G  740K  1.6G   1% /run/dev/disk/by-uuid/55421528-015b-4bfc-8490-74b4cc25a2b4  9.1G  8.2G  471M  95% /tmpfs                                                   5.0M     0  5.0M   0% /run/locktmpfs                                                   4.9G  536K  4.9G   1% /run/shm/dev/sdb6                                               203G  647M  192G   1% /homeWhat is taking so much space because I can't find any large files in /var/cache. I've tried with apt-get clean and apt-get autoremove, with no luck on getting more space. How can I find the files that are taking up so much space? How can I do it securely so I don't mess up some important files? Or do I need to increase the size of the partition instead? Edit:The output of du -sh /*0   /07.2M    /bin26M /boot0   /dev12M /etc4.0K    /example.conf.json588M    /home0   /initrd.img212M    /lib3.1M    /lib324.0K    /lib6416K /lost+found24K /media4.0K    /mnt1015M   /optdu: cannot access `/proc/15453/task/15453/fd/4': No such file or directorydu: cannot access `/proc/15453/task/15453/fdinfo/4': No such file or directorydu: cannot access `/proc/15453/fd/4': No such file or directorydu: cannot access `/proc/15453/fdinfo/4': No such file or directory0   /proc52M /root1.3M    /run9.5M    /sbin4.0K    /selinux8.0K    /srv0   /sys40K /tmp6.4G    /usr350M    /var0   /vmlinuzOutput of du -sh /usr/* | sort -rh:4.1G    /usr/share1.9G    /usr/lib382M    /usr/bin39M /usr/include36M /usr/sbin6.3M    /usr/lib321.9M    /usr/lib641.4M    /usr/x86_64-linux-gnu588K    /usr/local92K /usr/src36K /usr/var12K /usr/man4.0K    /usr/games
How to clean up the rootfs partition or increase the size
disk usage
Run du -x / >/tmp/du to generate a breakdown of disk usage per directory on the / filesystem (-x means don't traverse other filesystems).Your biggest consumers are:588M    /home 0.6GB of user data1015M   /opt 1GB of software that you installed manually6.4G    /usr  6.4GB of software installed via packages350M    /var 0.3GB of data used by system softwareNone of that is surprising. 9GB is plenty for a typical single-function server but it isn't very large for a desktop computer where users want to install all kinds of programs. You can use the following command to list installed packages sorted by size:dpkg-query -W -f='${Installed-Size;8}  ${Package}\n' | sort -nsee How do I list installed software with the installed size? for alternatives, including GUI ones. In particular, Synaptic lets you sort packages by size and is more convenient for removing packages on the fly. Of course, don't remove a package if you don't know what it does.