On Sat, 6 Dec 2014 02:02:50 PM Brett Pemberton wrote:
Can't comment on BTRFS.
The RAID5/6 code is very experimental and I wouldn't suggest trying to use that functionality for any data you're attached to. Stick to 2 drives, and good backups, for btrfs.
The 'mirror' RAID method of BTRFS is functionally the same as RAID5 from a 'you can lose one disk' point of view. BTRFS makes sure every piece of data is stored on 2 disks, so you can lose any one disk regardless of how big your array is. If there was such a thing as a 'always store 3 copies' mode then you could lose 2 disks from your array, which is functionally the same as RAID6 from that point of view. And depending on your workload this could be an improvement over RAID[56] from a performance point of view too (especially if you had a failed disk - that really hurts!) James