This is not a SFW instance. NSFW communities will be tagged, and efforts will be made to keep SFW communities clean, but proceed at your own comfort level.
btrfs’s handling makes sense. The kernel talks to the disk directly, the file is just a pointer for what range it uses, and a placeholder for the filesystem. Something like raid, balancing, cow, all won’t work because the kernel doesn’t even go through btrfs to change the swap"file".
If you want a proper file as swapfile, with the corresponding overhead, you can make a regular file and mount it via loopback then use it as a swap device.
btrfs’s handling makes sense. The kernel talks to the disk directly, the file is just a pointer for what range it uses, and a placeholder for the filesystem. Something like raid, balancing, cow, all won’t work because the kernel doesn’t even go through btrfs to change the swap"file".
If you want a proper file as swapfile, with the corresponding overhead, you can make a regular file and mount it via loopback then use it as a swap device.