1
On my Debian Linux laptop a couple of days ago I got my 23GB root EXT4 partition full (probably I installed more software than I expected).
Since I have plenty of space in my BTRFS home partition, 466GB of which 400GB available, I moved the contents of /usr/share/doc
into /home/share/doc
, and I created a link /usr/share/doc -> /home/share/doc
. The size of this doc
directory was around 2.4GB.
After this change, the system has been working correctly for the past 24 hours.
All at once I got the KDE menu bar and the desktop environment disappear, with only the applications' windows still open. I switched to the command line, and with df -h
I found out that all the 466GB of my home partition are used.
With tree --du -h .
from /home
, I get "4.8G used", a realistic figure.
So, who is right? df
or tree
? Where do the remaining 460GB come from?
Since the doc
directory I copied is still 2.4GB, I suspect that moving it and creating the link is not the reason of my problem.
How can I fix this and get a stable system back?
Update:
sudo btrfs filesystem usage -h -T /home
Overall:
Device size: 465.66GiB
Device allocated: 465.66GiB
Device unallocated: 0.00B
Device missing: 0.00B
Used: 464.28GiB
Free (estimated): 64.00KiB (min: 64.00KiB)
Data ratio: 1.00
Metadata ratio: 1.00
Global reserve: 490.34MiB (used: 0.00B)
Data Metadata System
Id Path single single single Unallocated
-- --------------- ---------- ----------- ----------- ------------
1 /dev/nvme0n1p9 463.65GiB 2.01GiB 4.00MiB 0.00B
-- --------------- ---------- ----------- ----------- ------------
Total 463.65GiB 2.01GiB 4.00MiB 0.00B
Used 463.65GiB 644.72MiB 80.00KiB 0.00B
Debian 9.5
Dell Precision 7720
home directory: BTRFS
/ directory: EXT4
3Three thoughts: (1) If a filesystem is full and files within sum up to a lot smaller size, it may be because some file(s) is still open (and maybe growing) after being unlinked. Assuming this is the case, some process probably has gone awry. (2) A Btrfs subvolume mounted elsewhere (or not at all) cannot be seen by
tree /home
, yetdf
prints what the filesystem as a whole reports to it. (3) Whatdf
prints for Btrfs mountpoints might be strange sometimes because calculating free space on Btrfs is tricky. You may get clearer… no, different picture withbtrfs filesystem df /mountpoint
. – Kamil Maciorowski – 2018-10-11T18:11:05.540@KamilMaciorowski - I updated my question. – Pietro – 2018-10-12T09:25:39.337