I don’t use BTRFS raid, I don’t actually use any RAID. I use SnapRAID which is really more of a parity system than real RAID.
I have a bunch of data disks that are formatted BTRFS, then 2 parity disks formatted using ext4 since they don’t require any BTRFS features. Then I use snapraid-btrfs which is a wrapper around SnapRAID to automatically generate BTRFS snapshots on the data disks when doing a SnapRAID sync.
Since the parity is file based, it’s best to use it with snapshots, so that’s the solution I went with. I’m sure you could also use LVM snapshots with ext4 or ZFS snapshots, but BTRFS with SnapRAID is well supported and I like how BTRFS snapshots/subvolumes works so I went with that. Also BTRFS has some nice features over ext4 like CoW and checksumming.
I considered regular RAID but I don’t need the bandwidth increase over single disks and I didn’t ever want the chance of losing a whole RAID pool. With my SnapRAID setup I can lose any 2 drives and not lose any data, and if I lose 3 drives, I only lose the data on any lost data drives, not all the data. Also it’s easy to add a single drive at a time as I need more space. That was my thought process when choosing it anyway and it’s worked for my use case (I don’t need much IOPS or bandwidth, just lots of cheap fairly resilient and easy to expand storage).
I have a bunch of data disks that are formatted BTRFS, then 2 parity disks formatted using ext4 since they don’t require any BTRFS features. Then I use snapraid-btrfs which is a wrapper around SnapRAID to automatically generate BTRFS snapshots on the data disks when doing a SnapRAID sync.
Since the parity is file based, it’s best to use it with snapshots, so that’s the solution I went with. I’m sure you could also use LVM snapshots with ext4 or ZFS snapshots, but BTRFS with SnapRAID is well supported and I like how BTRFS snapshots/subvolumes works so I went with that. Also BTRFS has some nice features over ext4 like CoW and checksumming.
I considered regular RAID but I don’t need the bandwidth increase over single disks and I didn’t ever want the chance of losing a whole RAID pool. With my SnapRAID setup I can lose any 2 drives and not lose any data, and if I lose 3 drives, I only lose the data on any lost data drives, not all the data. Also it’s easy to add a single drive at a time as I need more space. That was my thought process when choosing it anyway and it’s worked for my use case (I don’t need much IOPS or bandwidth, just lots of cheap fairly resilient and easy to expand storage).