snap /dev/loop at 100% utilization -- no free space

Question

Free space:

thufir@dur:~$ 
thufir@dur:~$ df -h
Filesystem                   Size  Used Avail Use% Mounted on
udev                         3.9G     0  3.9G   0% /dev
tmpfs                        794M  9.8M  785M   2% /run
/dev/mapper/ubuntu--vg-root  220G   37G  173G  18% /
tmpfs                        3.9G   35M  3.9G   1% /dev/shm
tmpfs                        5.0M  4.0K  5.0M   1% /run/lock
tmpfs                        3.9G     0  3.9G   0% /sys/fs/cgroup
/dev/loop0                    42M   42M     0 100% /snap/docker/171
/dev/loop1                    84M   84M     0 100% /snap/core/3440
/dev/loop3                    17M   17M     0 100% /snap/ubuntu-make/116
/dev/loop4                   232M  232M     0 100% /snap/vuze-vs/2
/dev/loop6                    17M   17M     0 100% /snap/ubuntu-make/109
/dev/loop7                    84M   84M     0 100% /snap/core/3247
/dev/loop8                   128K  128K     0 100% /snap/hello-world/27
/dev/loop2                    77M   77M     0 100% /snap/drakon/1
/dev/sda1                    511M  4.6M  507M   1% /boot/efi
tmpfs                        794M   16K  794M   1% /run/user/121
/dev/loop9                    17M   17M     0 100% /snap/ubuntu-make/123
tmpfs                        794M  2.2M  792M   1% /run/user/1000
/home/thufir/.Private        220G   37G  173G  18% /home/thufir
thufir@dur:~$ 

The snap images are at 100%. Is this a problem? If so, what's the solution?

Solution

No, having Snap images which consume 100% of their filesystem is perfectly acceptable. In fact, it's supposed to work that way.

A snap is a squashfs file carrying content and a bit of metadata that tells the system how to manipulate it. - https://docs.snapcraft.io/snaps/metadata

Because Snap uses SquashFS, which is a compressed read-only filesystem, the filesystem size is always just large enough to contain it's contents. In addition, because the filesystem is read-only, there's no need to allow for any additional storage, as such additional space can never be used anyway.