Can someone point me to the response that resolves the OP's issue?

From: https://www.linuxquestions.org/quest...2/#post6050831

(I am having a similar issue but not savvy enough to figure out how to resolve.)
fairway-MS-7A71 ~ # df -h
Filesystem Size Used Avail Use% Mounted on
udev 7.8G 0 7.8G 0% /dev
tmpfs 1.6G 9.5M 1.6G 1% /run
/dev/sda5 62G 14G 45G 24% /
tmpfs 7.9G 79M 7.8G 1% /dev/shm
tmpfs 5.0M 4.0K 5.0M 1% /run/lock
tmpfs 7.9G 0 7.9G 0% /sys/fs/cgroup
/dev/loop0 194M 194M 0 100% /snap/mailspring/402
/dev/loop2 55M 55M 0 100% /snap/core18/1223
/dev/loop1 55M 55M 0 100% /snap/core18/1265
/dev/loop4 45M 45M 0 100% /snap/gtk-common-themes/1353
/dev/loop3 43M 43M 0 100% /snap/gtk-common-themes/1313
/dev/loop5 90M 90M 0 100% /snap/core/7917
/dev/loop6 90M 90M 0 100% /snap/core/8039
/dev/loop7 194M 194M 0 100% /snap/mailspring/407
/dev/sdc2 481G 36G 421G 8% /media/fairway/BackupStorage
cgmfs 100K 0 100K 0% /run/cgmanager/fs
tmpfs 1.6G 52K 1.6G 1% /run/user/1000

Thanks F

You don't tell us what version/distro of Linux, but the solution is to remove files you're not using, and free up some disk space. Seems you have several things mounted as loopback devices (guessing...no details provided). What error(s)/message(s)/problem(s) are you actually having?

Fairway,
Welcome to LinuxQuestions. As posted why do you think you have a similar problem?

If you are asking about the /dev/loop devices being 100%, they are virtual devices that are read only and therefore is normal.

1 members found this post helpful.

Thought I was posting in the mint forum.... Dual boot Win10/Mint 18.3 Cinnamon
I intermittently receive an error "Low Disk Space On Filesystem Root"... "The volume filesystem root has 0 bytes disk space remaining..."
(I would upload a screenshot but doenst look like i can on the forum)
Maybe I shouldnt have tagged on to this post if its just referring to virtual space. I dont know what to delete to get some space back so the warning mentioned stops popping up.

Ive been running this install for a couple of years with no issues other then the occasional warning noted.
Thanks. F

root on sda5 is at 24% from what you posted.

Is this a VM that is full? Need more info.

You can upload long text or image to:
http://sprunge.us
http://ix.io/
https://0x0.st

When you get that warning, look at this entry in the df output:
Use% will be very high.
When that happens, you need to see what's filling up your root filesystem. Probably it's a runaway/not rotated log file.

gives a breakdown of approximate usage by top-level directory.

For some reason, it shows a large usage by my /mnt directory - which only contains mountpoints for (mounted) filesystems on a second disk.
It will also show some failed attempts at reading missing /proc entries which can obviously be ignored.

This morning the following popup occurred:
Low Disk Space on "Filesystem root"
The volume "Filesystem root" has only 646.5 MB disk space remaining.
Here is the output from the two suggestions after receiving the warning-
Filesystem 1K-blocks Used Available Use% Mounted on
udev 8163984 0 8163984 0% /dev
tmpfs 1639044 9584 1629460 1% /run
/dev/sda5 64025396 14786352 45963744 25% /
tmpfs 8195212 65016 8130196 1% /dev/shm
tmpfs 5120 4 5116 1% /run/lock
tmpfs 8195212 0 8195212 0% /sys/fs/cgroup
/dev/sdc2 503833832 38040012 440177436 8% /media/fairway/BackupStorage
cgmfs 100 0 100 0% /run/cgmanager/fs
/dev/loop0 91264 91264 0 100% /snap/core/8039
/dev/loop2 55936 55936 0 100% /snap/core18/1223
/dev/loop1 45312 45312 0 100% /snap/gtk-common-themes/1353
/dev/loop3 55936 55936 0 100% /snap/core18/1265
/dev/loop5 43904 43904 0 100% /snap/gtk-common-themes/1313
/dev/loop6 198016 198016 0 100% /snap/mailspring/402
/dev/loop4 198016 198016 0 100% /snap/mailspring/407
/dev/loop7 91264 91264 0 100% /snap/core/7917
tmpfs 1639044 24 1639020 1% /run/user/1000
78M /boot
3.9M /lib32
5.1G /usr
664K /root
19M /sbin
du: cannot access '/run/user/1000/gvfs': Permission denied
9.4M /run
du: cannot access '/proc/15530/task/15530/fd/4': No such file or directory
du: cannot access '/proc/15530/task/15530/fdinfo/4': No such file or directory
du: cannot access '/proc/15530/fd/3': No such file or directory
du: cannot access '/proc/15530/fdinfo/3': No such file or directory
0 /proc
0 /sys
4.0K /lib64
2.8G /snap
1.5M /dev
4.0K /mnt
37G /media
144K /tmp
555M /lib
5.4G /home
4.0K /cdrom
2.3G /var
16K /lost+found
4.0K /srv
476M /opt
77M /etc
32K /timeshift
16M /bin
54G /

Do you have any sort of automatic backup program running?

I have Timeshift set to do a daily snapshot.

How is Timeshift configured? I would guess it is writing the snapshot to your root partition which fills up the space causing the displayed message, the snapshot is then deleted.

The Timeshift snapshot location is set to /dev/sdc2 which is a 2TB external drive of which I allocated ~.5Gb to Linux (has ~470Gb free)
I just disabled Timeshift to see if that helps. I will post again the next time the error pops up (or try any other suggestions).
Thanks for taking a look.
F

I have 15GB used out of a 39GB Timeshift partition - it can be quite a big thing and needs careful configuration.

Do you have anything that uses lots of space on your / partition such as /var/log or /tmp etc?

Is /media only used as a mount point or does it contain "real" files?