[ Thanks to An Anonymous Reader for
this link. ]
“It is important that we perform well, but we wanted to make
sure Btrfs had features that other Linux filesystems could not
easily provide.“The biggest single feature is the copy on write snapshotting,
which is actually the basis of most of the other advanced features
in the FS. Btrfs snapshots are writable and can be snapshotted
again.“Data and metadata checksums are also a key part of making sure
we can administer the storage over time. We need to be able to
detect when the disk is giving us the wrong data, and try to
correct it by grabbing data from another mirror or sending a
command down to the disk array to ask for another copy. This
command doesn’t exist yet, but we do plan on adding it to the
Linux software raid stack at least.”