Quote Originally Posted by drag View Post
Plus most of BTRFS features are worthless if all you have is a single disk. The ability to do parities, checksums, scrub disks, etc etc are going to be of little use without any ability to recover corrupt data. For that you need at least 2 disks.
That's only true if your entire disk dies. Otherwise, Btrfs keeps backup information in several places on the disk and can recover from them once it finds that there is corruption. COW also helps with that, if a newer version of the file is corrupt, it can at least restore the last known good version of the file.