Disk Usage Analyzer is a graphical, menu-driven application to analyse disk usage in a GNOME environment. It can easily scan either the whole filesystem tree, or a specific user-requested directory branch (local or remote).
1-1. mate-disk-usage-analyzer is also from baobab.
1-2. It scans filesystem or directory
sudo du -sh /*
2. http://manpages.ubuntu.com/manpages/zes ... /du.1.html
Summarize disk usage of the set of FILEs, recursively for directories.
3. http://manpages.ubuntu.com/manpages/xen ... sck.8.html
fsck - check and repair a Linux filesystem
fsck is used to check and optionally repair one or more Linux filesystems.
3-1. fsck is the default check and repair tool of filesystems (include directories）for Ubuntu.
3-2. http://manpages.ubuntu.com/manpages/xen ... tab.5.html
fstab - static information about the filesystems
3-2-1. The sixth field (fs_passno) in those lines which mount every filesystem in /etc/fstab decides the fsck behavior when your pc boots.
The sixth field (fs_passno).
This field is used by fsck(8) to determine the order in which filesystem checks are done at boot time. The root filesystem should be specified with a fs_passno of 1. Other filesystems should have a fs_passno of 2. Filesystems within a drive will be checked sequentially, but filesystems on different drives will be checked at the same time to utilize parallelism available in the hardware. Defaults to zero (don't fsck) if not present.
3-2-2. It will run the fsck command at next
reboot every time when your PC encountered an abnormal
3-3. You may also execute the fsck command manually anytime you want.
3-4. The read / write / scan efficiency may become better everytime after your PC was run with fsck command.
The term "Session" is presumed to be a desktop environment
4. Session means XSession
knowing how to create X session scripts can grant you greater flexibility in customizing your desktop environment whether you use GNOME, KDE, XFCE, Openbox or other lesser-known window managers like Blackbox or FVWM.
4-2. https://en.wikipedia.org/wiki/X_display ... gram_type)
In the X Window System, an X display manager is a graphical login manager which starts a session on an X server from the same or another computer.
4-3. Lightdm is the default X display manager in Ubuntu
4-3-2. https://wiki.ubuntu.com/CustomXSession# ... figuration
4-4. MDM is the default X display manager in Ubuntu Mate
MDM Display Manager