0

I have a problem with hidden disk usage on my Ubuntu 22.04. As you can see, the ncdu utility only finds ~30GB on the system:

enter image description here

Whereas Ubuntu's System Monitor finds that 88 GB are being used:

enter image description here

What's going on here?

Output of df -h:

enter image description here

KSHMR
  • 101
  • 1
  • I also wonder where this "Apparent size: 128 Tb" comes from. – Jos May 26 '23 at 16:10
  • The red ! at the start of many of the entries means there is an error while reading the directory. I guess that might be an ownership issue so try it with sudo. Did you use the -x option? That stops the scan crossing filesystem boundaries. Without the -x I too get the crazy high 128TB. With the -x option I get a realistic number. So try sudo ncdu -x / – PonJar May 26 '23 at 20:16
  • Files can be invisible (but using disk space) for several reasons. Programs can create temporary files, open, unlink, and use them very privately, with guaranteed deletion no matter how the program exits. Files can get really big, if some budding sysadmin deleting a log file that some process has open (and is about to write block N+1) without notice. You can investigate open files with sudo lsof, followed by lots of options. Read man lsof sudo. – waltinator May 27 '23 at 01:13
  • https://askubuntu.com/questions/5980/how-do-i-free-up-disk-space – Hannu May 27 '23 at 07:08

0 Answers0