On Wed, May 25, 2016 at 10:58 AM, H. Peter Anvin <h...@zytor.com> wrote: > Hi, > > I'm looking at using a btrfs with snapshots to implement a generational > backup capacity. However, doing it the naïve way would have the side > effect that for a file that has been partially modified, after > snapshotting the file would be written with *mostly* the same data. How > does btrfs' COW algorithm deal with that? If necessary I might want to > write some smarter user space utilities for this.
Assuming 'snapshots' plural refers incremental snapshots of a subvolume, you might want to use the send ioctl of the kernel. Userspace btrfs-progs btrfs send --no-data output might give some hints. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
