incorrect information wrt used and free:

[MangoIV]

duf outputs:

╭───────────────────────────────────────────────────────────────────────────────────────────────╮
│ 3 local devices                                                                               │
├────────────┬────────┬────────┬────────┬───────────────────────────────┬──────┬────────────────┤
│ MOUNTED ON │   SIZE │   USED │  AVAIL │              USE%             │ TYPE │ FILESYSTEM     │
├────────────┼────────┼────────┼────────┼───────────────────────────────┼──────┼────────────────┤
│ /          │ 907.8G │ 487.8G │ 373.8G │ [##########..........]  53.7% │ ext4 │ /dev/vg/root   │
│ /boot      │ 498.7M │ 357.2M │ 141.5M │ [##############......]  71.6% │ vfat │ /dev/nvme0n1p1 │
│ /nix/store │ 907.8G │ 487.8G │ 373.8G │ [##########..........]  53.7% │ ext4 │ /dev/vg/root   │
╰────────────┴────────┴────────┴────────┴───────────────────────────────┴──────┴────────────────╯

as you can see, the used and avail don't sum up to size, they pretty much miss exactly the size of my home folder.

[IGLOU-EU]

Hi @MangoIV
This is probably the reserved blocks on EXT4 filesystem. By default, an ext4 FS reserve 5% of its capacity for special processes.

Used and Avail are rounded value but:
Reserved space: 907.8*5/100=45.39
487.8+373.8+45.39=906.99

[MangoIV]

Still where's my /home? It's around 60 GB, according to duf, the nix store is all I have in my disk

[IGLOU-EU]

My bad, you are under NixOs.
Send the result of df -h and mount

[MangoIV]

Filesystem           Size  Used Avail Use% Mounted on
/dev/mapper/vg-root  908G  505G  358G  59% /
tmpfs                6.9G   15M  6.8G   1% /run
devtmpfs             1.4G     0  1.4G   0% /dev
tmpfs                 14G   68M   14G   1% /dev/shm
tmpfs                 14G  456K   14G   1% /run/wrappers
/dev/nvme0n1p1       499M  211M  288M  43% /boot
tmpfs                2.8G   44K  2.8G   1% /run/user/1000

/dev/mapper/vg-root on / type ext4 (rw,relatime)
tmpfs on /run type tmpfs (rw,nosuid,nodev,size=7141100k,nr_inodes=819200,mode=755)
devtmpfs on /dev type devtmpfs (rw,nosuid,size=1428220k,nr_inodes=3567556,mode=755)
devpts on /dev/pts type devpts (rw,nosuid,noexec,relatime,gid=3,mode=620,ptmxmode=666)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
proc on /proc type proc (rw,nosuid,nodev,noexec,relatime)
ramfs on /run/keys type ramfs (rw,nosuid,nodev,relatime,mode=750)
tmpfs on /run/wrappers type tmpfs (rw,nodev,relatime,mode=755)
sysfs on /sys type sysfs (rw,nosuid,nodev,noexec,relatime)
/dev/mapper/vg-root on /nix/store type ext4 (ro,relatime)
none on /run/agenix.d type ramfs (rw,nosuid,nodev,relatime,mode=751)
securityfs on /sys/kernel/security type securityfs (rw,nosuid,nodev,noexec,relatime)
cgroup2 on /sys/fs/cgroup type cgroup2 (rw,nosuid,nodev,noexec,relatime,nsdelegate,memory_recursiveprot)
pstore on /sys/fs/pstore type pstore (rw,nosuid,nodev,noexec,relatime)
efivarfs on /sys/firmware/efi/efivars type efivarfs (rw,nosuid,nodev,noexec,relatime)
bpf on /sys/fs/bpf type bpf (rw,nosuid,nodev,noexec,relatime,mode=700)
hugetlbfs on /dev/hugepages type hugetlbfs (rw,relatime,pagesize=2M)
mqueue on /dev/mqueue type mqueue (rw,nosuid,nodev,noexec,relatime)
debugfs on /sys/kernel/debug type debugfs (rw,nosuid,nodev,noexec,relatime)
fusectl on /sys/fs/fuse/connections type fusectl (rw,nosuid,nodev,noexec,relatime)
configfs on /sys/kernel/config type configfs (rw,nosuid,nodev,noexec,relatime)
ramfs on /run/credentials/systemd-sysctl.service type ramfs (ro,nosuid,nodev,noexec,relatime,mode=700)
ramfs on /run/credentials/systemd-tmpfiles-setup-dev.service type ramfs (ro,nosuid,nodev,noexec,relatime,mode=700)
/dev/nvme0n1p1 on /boot type vfat (rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro)
ramfs on /run/credentials/systemd-tmpfiles-setup.service type ramfs (ro,nosuid,nodev,noexec,relatime,mode=700)
tmpfs on /run/user/1000 type tmpfs (rw,nosuid,nodev,relatime,size=2856436k,nr_inodes=714109,mode=700,uid=1000,gid=100)
portal on /run/user/1000/doc type fuse.portal (rw,nosuid,nodev,relatime,user_id=1000,group_id=100)
gvfsd-fuse on /run/user/1000/gvfs type fuse.gvfsd-fuse (rw,nosuid,nodev,relatime,user_id=1000,group_id=100)

[IGLOU-EU]

Thanks.
As you can see, you don't have a /home mount point. So duf can't display it.
You can use the -all option with duf, to see everything, including tmpfs file system.

[MangoIV]

Do I understand something wrong here?
Afaiu:

• /nix/store is part of / so it should be only part of what is shown for /, so how can the used and free for them be the same? /nix/store is not the whole /?