/home full due to unallocated space on LUKS btrfs partition

Ask Fedora
1

Hello !

I am a little bit stuck on a problem that I’m not sure how to solve.
I was downloading some big files today on my main 350Gb “/” and “/home” LUKS-encrypted Btrfs partition, until the system told me I was running off of available space.
I don’t really understand how, because only 198Gb are used.
GParted tells me there is a problem with unallocated space in the partition, but offers no way to fix it.
Do you have any idea of how to make the /home partition fill the remaining space ?
In the attachements the screenshots of the the logical volume, disk analyzer and GParted

Thank you very much for any help you can give !

Capture d’écran du 2024-12-12 14-27-27
Capture d’écran du 2024-12-12 14-27-27651×631 52.8 KB

Capture d’écran du 2024-12-12 14-28-02
Capture d’écran du 2024-12-12 14-28-02786×312 9.96 KB

Capture d’écran du 2024-12-12 14-35-13
Capture d’écran du 2024-12-12 14-35-13968×670 116 KB

2

With a default installation on btrfs both / and /home share the same file system. The 350G you have available is shared by both.

There are some cases where the file system has indicated full even though it does not have that much data and it seems that may have been caused by failure of btrfs to release the count of used inodes or btree pointers.

I suggest using a couple of the btrfs cleanup commands (I am not familiar enough with btrfs to name them) to perform cleanup and recovery so the system can use the remaining space. I am sure someone who uses a btrfs system can step in and provide further guidance.

Looking at that image from gparted and the middle image (directly above gparted) it seems possible that the partition may have been resized (expanded) without also resizing the file system in the partition. It may be necessary to use btrfs command from the command line (cli) to expand the file system. Indications are that the file system is ~200G while the partition is 350G

What is the output of lsblk -f and df -h?
Please post those as preformatted text using the </> button on the toolbar of the text input screen. Copy and paste the text, then highlight the text before clicking that button.

3

Hello ! Thank you for your answer
Here the requested info :

NAME                                          FSTYPE      FSVER LABEL    FSAVAIL FSUSE% MOUNTPOINTS
zram0                                                                                   [SWAP]
nvme0n1                                                                                                                      
├─nvme0n1p1                                   vfat        FAT32          552,3M      8% /boot/efi
├─nvme0n1p2                                   ext4        1.0              490,7M    43% /boot
├─nvme0n1p3                                   crypto_LUKS 2                             
│ └─luks-_________________________            btrfs             fedora00      4G     97% /home
│                                                                                         /
├─nvme0n1p4                                                                                                                  
└─nvme0n1p5                                   ntfs

(i just erased the UUIDs, I’m not sure if it safe to post them online)

and

Sys. de fichiers Taille Utilisé Dispo Uti% Monté sur
/dev/dm-0          189G    184G  4,1G  98% /
devtmpfs           4,0M       0  4,0M   0% /dev
tmpfs              2,9G     96K  2,9G   1% /dev/shm
efivarfs           154K     63K   87K  42% /sys/firmware/efi/efivars
tmpfs              1,2G    2,0M  1,2G   1% /run
tmpfs              1,0M       0  1,0M   0% /run/credentials/systemd-cryptsetup@luks\___________\_______\_______\_______\_______________.service
tmpfs              1,0M       0  1,0M   0% /run/credentials/systemd-journald.service
tmpfs              1,0M       0  1,0M   0% /run/credentials/systemd-network-generator.service
tmpfs              1,0M       0  1,0M   0% /run/credentials/systemd-udev-load-credentials.service
tmpfs              1,0M       0  1,0M   0% /run/credentials/systemd-sysctl.service
tmpfs              1,0M       0  1,0M   0% /run/credentials/systemd-tmpfiles-setup-dev-early.service
tmpfs              1,0M       0  1,0M   0% /run/credentials/systemd-tmpfiles-setup-dev.service
/dev/dm-0          189G    184G  4,1G  98% /home
tmpfs              2,9G     16K  2,9G   1% /tmp
/dev/nvme0n1p2     974M    416M  491M  46% /boot
/dev/nvme0n1p1     599M     47M  553M   8% /boot/efi
tmpfs              1,0M       0  1,0M   0% /run/credentials/systemd-vconsole-setup.service
tmpfs              1,0M       0  1,0M   0% /run/credentials/systemd-tmpfiles-setup.service
tmpfs              1,0M       0  1,0M   0% /run/credentials/systemd-resolved.service
tmpfs              580M    9,6M  571M   2% /run/user/1000

(again took some info out)

Hope it helps !

4

It seems like a filesystem resizing issue.
To resolve it and use all the available space in the Btrfs partition:
sudo btrfs filesystem resize max /

You can display detailed filesystem usage information with:
sudo btrfs filesystem usage -T /

I hope this helps.

6

Thank you Emanuele, you were right :+1:

The second command reported 161Gb as device slack, and the first command made the btrfs partition use all of the partition space
It is now working as intended !

Thank you very much !

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