Cbt — Linux

: Persistent, kernel-supported, accurate for thin volumes. Cons : Only works with LVM thin volumes, not raw disks or standard partitions. 3.4. Btrfs / ZFS Native Change Tracking Btrfs has btrfs send with snapshots: It efficiently computes differences between snapshots using a change-tracking mechanism. No explicit per-block bitmap is exposed, but btrfs send -p <parent> only sends changed extents.

# Create thin pool and thin volume lvcreate -L 10G --thinpool vg0/thinpool lvcreate -T vg0/thinpool -V 5G -n origin lvcreate -s vg0/origin -n snap1 After some writes, create second snapshot lvcreate -s vg0/origin -n snap2 Find changed blocks between snap1 and snap2 thin_delta /dev/mapper/vg0-thinpool --snap1 snap1 --snap2 snap2 linux cbt

has zfs diff and zfs send -i for incremental streams. Internally, ZFS uses transaction groups and block pointers to identify changed blocks. : Persistent, kernel-supported, accurate for thin volumes