How to remove /dev/loops [duplicate]
On my Ubuntu desktop, the command fdisk -l shows /dev/loopX up to /dev/loop23. I'm using gnome-fallback on Ubuntu 18.04 LTS.
I'm wondering what possible effects these could have on performance and stabilty of the OS, and if they are just superfluous, how can I remove them?
root@pc5:~# fdisk -l
...
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop15: 3.7 MiB, 3821568 bytes, 7464 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop16: 54.6 MiB, 57274368 bytes, 111864 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop17: 140.7 MiB, 147501056 bytes, 288088 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop18: 14.8 MiB, 15462400 bytes, 30200 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop19: 42.8 MiB, 44879872 bytes, 87656 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop20: 54.5 MiB, 57151488 bytes, 111624 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop21: 4.2 MiB, 4403200 bytes, 8600 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop22: 153.5 MiB, 160935936 bytes, 314328 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/loop23: 140.7 MiB, 147501056 bytes, 288088 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
output of df:
Filesystem 1K-blocks Used Available Use% Mounted on
udev 8128184 0 8128184 0% /dev
tmpfs 1630464 3716 1626748 1% /run
/dev/sda2 229184876 63255488 154217748 30% /
tmpfs 8152300 142672 8009628 2% /dev/shm
tmpfs 5120 4 5116 1% /run/lock
tmpfs 8152300 0 8152300 0% /sys/fs/cgroup
/dev/loop2 160512 160512 0 100% /snap/gnome-3-28-1804/110
/dev/loop3 4352 4352 0 100% /snap/gnome-calculator/544
/dev/loop0 3840 3840 0 100% /snap/gnome-system-monitor/111
/dev/loop4 91264 91264 0 100% /snap/core/8039
/dev/loop1 1024 1024 0 100% /snap/gnome-logs/81
/dev/loop6 87936 87936 0 100% /snap/shotcut/55
/dev/loop5 406528 406528 0 100% /snap/redis-desktop-manager/332
/dev/loop8 91264 91264 0 100% /snap/core/8213
/dev/loop7 406656 406656 0 100% /snap/redis-desktop-manager/335
/dev/loop9 15104 15104 0 100% /snap/gnome-characters/367
/dev/loop11 157184 157184 0 100% /snap/chromium/949
/dev/loop12 87808 87808 0 100% /snap/shotcut/53
/dev/loop13 1024 1024 0 100% /snap/gnome-logs/73
/dev/loop14 45312 45312 0 100% /snap/gtk-common-themes/1353
/dev/loop16 55936 55936 0 100% /snap/core18/1279
/dev/loop15 3840 3840 0 100% /snap/gnome-system-monitor/107
/dev/loop10 159872 159872 0 100% /snap/gnome-3-28-1804/91
/dev/loop17 144128 144128 0 100% /snap/gnome-3-26-1604/97
/dev/sda1 523248 6232 517016 2% /boot/efi
/dev/loop18 15104 15104 0 100% /snap/gnome-characters/359
/dev/loop19 43904 43904 0 100% /snap/gtk-common-themes/1313
/dev/loop20 55936 55936 0 100% /snap/core18/1265
/dev/loop21 4352 4352 0 100% /snap/gnome-calculator/536
/dev/loop22 157184 157184 0 100% /snap/chromium/958
/dev/loop23 144128 144128 0 100% /snap/gnome-3-26-1604/98
/dev/sdb1 492127240 409174612 57930932 88% /home
tmpfs 1630460 16 1630444 1% /run/user/121
tmpfs 1630460 140 1630320 1% /run/user/1001
tmpfs 1630460 0 1630460 0% /run/user/0
Edit for sudo fdisk -l
The question was changed today so here is how you can remove the extra output without resorting to deleting all your snaps and being left without a calculator and what not:
sudo fdisk -l | sed -e '/Disk \/dev\/loop/,+5d'
As this can be hard to remember you could create an alias in your ~/.bashrc:
alias fdsk="sudo fdisk -l | sed -e '/Disk \/dev\/loop/,+5d'"
Then simply type fdsk in the command line and enter your password when prompted.
As mentioned in comments /dev/loop99 are snap file system images described here:
- Small snap loop devices visible in gnome-disk-utility OR what is the function of snap ubuntu-core
Assuming you don't want to uninstall all your snaps, your next best option is to hide them from output by appending | grep -v ^/dev/loop. For example:
$ df | grep -v ^/dev/loop
Filesystem 1K-blocks Used Available Use% Mounted on
udev 3978476 0 3978476 0% /dev
tmpfs 802400 1688 800712 1% /run
/dev/nvme0n1p6 46445360 33133368 11159560 75% /
tmpfs 4011984 227448 3784536 6% /dev/shm
tmpfs 5120 4 5116 1% /run/lock
tmpfs 4011984 0 4011984 0% /sys/fs/cgroup
/dev/nvme0n1p8 9485308 1890272 7595036 20% /mnt/e
/dev/nvme0n1p10 27937812 22501880 3993732 85% /mnt/clone
/dev/nvme0n1p7 23734708 19316220 3189796 86% /mnt/old
/dev/nvme0n1p4 380829660 169799196 211030464 45% /mnt/c
/dev/nvme0n1p2 97280 33222 64058 35% /boot/efi
/dev/sda3 963668988 43929712 919739276 5% /mnt/d
tmpfs 802400 60 802340 1% /run/user/1000
All your loop mounted devices appear to be snaps. If (as you've indicated) you really don't want any of them refer to man snap.
Here's the related excerpt:
remove
Remove snaps from the system
The remove command removes the named snap instance from the system.
By default all the snap revisions are removed, including their data and the common data direc‐
tory. When a --revision option is passed only the specified revision is removed.
Usage: snap remove [remove-OPTIONS]
--no-wait
Do not wait for the operation to finish but just print the change id.
--revision
Remove only the given revision
--purge
Remove the snap without saving a snapshot of its data
and an example:
snap remove --purge gphoto2
As mentioned on the man page the --purge switch removes the snap without saving a snapshot of its data. As mentioned in this comment you may wish to find non-snap alternatives to these snap apps.
The Ubuntu Package Search page may be useful in helping you with the search for deb packages with corresponding features.
Attention: As mentioned in this answer While you could unmount the directory and delete the core snap, you'd break all installed snaps doing this, and the system will make it hard for you to do that as a result.
As a side note, it's important to understand that snap packages strengths and weaknesses are the same and much of the criticism surrounding these packages is the same as the accolades. Automatic updating of snaps is both hated and loved depending on who you ask. The read only loop mounted snaps are a boon to some and an annoyance to others. You can find out more about that at https://en.wikipedia.org/wiki/Snappy_(package_manager)
Many of the articles referenced in the Wikipedia article are worth reading as well.