I’m attempting a new install. I want to use btrfs with swapfile.

Do I need to disable compression on my swap subvolume?

Is there anything else I should keep in mind for fstab if I want to, say, not keep track of my Downloads folder when snapshotting?

Here is my fstab:

LABEL=arch@btrfs        /               btrfs           rw,relatime,discard=async,space_cache=v2,subvolid=256,subvol=>

LABEL=arch@btrfs        /home           btrfs           rw,relatime,discard=async,space_cache=v2,subvolid=257,subvol=>

LABEL=arch@btrfs        /var/cache/pacman/pkg   btrfs           rw,relatime,discard=async,space_cache=v2,subvolid=259>

LABEL=arch@btrfs        /var/log        btrfs           rw,relatime,discard=async,space_cache=v2,subvolid=258,subvol=>

LABEL=arch@btrfs        /.snapshots     btrfs           rw,relatime,discard=async,space_cache=v2,subvolid=260,subvol=>

LABEL=arch@btrfs        /swap           btrfs           rw,relatime,discard=async,space_cache=v2,subvolid=263,subvol=>

LABEL=efi@fat32         /efi            vfat            rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=asci>

/swap/swapfile          none            swap            defaults        0 0
  • ActualOPEnglish
    2•9 months ago

    “subvolume - cannot be snapshotted if it contains any active swapfiles”

    Make a subvolume only for the swapfile.

    has a chance to fragment

    This is true for all files. Is it a bigger problem for swap?

    has issues with hibernation (that I’ve personally encountered multiple times)

    This one I can’t refute. How long ago did you have these issues?

    • recursive_recursion [they/them]AEnglish
      3•9 months ago

      Make a subvolume only for the swapfile.

      doesn’t this kinda defeat the purpose/benefits of using a swapfile?

      This is true for all files. Is it a bigger problem for swap?

      specificly swapfiles yes, for swap partitions nope

      How long ago did you have these issues?

      Dec 2022, was still using and testing with swapfiles then and said fuck it as it caused too much problems.

      I can’t rule out user error till I retest and strictly “follow the guide to the T” as I made modifications while following the same Arch guide for swapfile with BTRFS

      edit:
      also for clarification, I’m still not sure which one is optimal/best as I initially thought that using swapfile was forward thinking for the future, I’m using and recommending swap partitions as it seems to be the easiest to implement once and use continuously without any problems atm.

      • @Supermariofan67
        2•9 months ago

        The reason I use a swap file is so that I can have only one partition backed by LUKS disk encryption, rather than having to screw around with lvm which comes with its own performance overhead and all. I’ve personally never had issues hibernating to.it, but given how much buggy uefi firmware is out there I’m not surprised to hear that other have issues