How to get rid of the “scanning for btrfs file systems” at start-up?

On Ubuntu 18.04 you can uninstall btrfs-support with

apt purge btrfs-progs

But that probably wouldn't save you much boot time. On my system the reason was, that I don't have a swap partition but on boot it is searched for such for about 30 seconds (while displaying the btrfs-scan).

remove the swap check

• open /etc/initramfs-tools/conf.d/resume
• replace RESUME=UUID=xxx with RESUME=none
• issue sudo update-initramfs -u
• reboot your system

(create the file if it does not exist and just add RESUME=none in it)

source: https://askubuntu.com/a/1034952/34298

The btrfs-tools package adds an action to the initramfs to load the btrfs module. If you purge that package (sudo apt-get purge btrfs-tools), followed by an update-initramfs -ukall if the uninstallation doesn't do it already, that should go away (though I've not tested it). If it doesn't, you can always blacklist the brtfs module in /etc/modprobe.d.

Btrfs isn’t too much stable to be used as deafult file-system. Most Linux distributions, probable all, are still using ext4 as primary file-system. So, you can completely remove it from your computer. Try the given command:

sudo apt-get purge btrfs-tools

This command will remove btrfs-tools from your computer. You may need to wait some minutes to complete the process. Your initramfs should be updated automatically but if not happen, do it by this command:

sudo update-initramfs -ukall

Then make a grub update:

sudo update-grub

All is well. Now make a restart. Hope your Ubuntu will start successfully this time.

Reference: http://www.ugcoder.com/disable-scanning-for-btrfs-file-systems-in-ubuntu/

Let me know if you have some questions still.