I'm running into an issue where my computer hangs for close to 30 seconds on "scanning for btrfs file systems" during boot. I don't have any btrfs filesystems. I tried removing btrfs-tools and updating grub as described here. However, that didn't change anything.* The second answer in that link says that the culprit is really a scan for a swap partition. My computer has an SSD with Linux on an LVM, and the LVM is composed of a root block and a swap block. If the problem is the search for a swap partition and I disable the swap check, will the swap block still be available to deal with running out of memory and save my computer from crashing?
*Further complicating things, I have an issue with grub-update not updating the timeout as described here. It might be that grub-update isn't removing the btrfs check either; but it seems unlikely, as I was able to use grub-update to remove the splash screen and show the boot process text in the first place.