I have no experience with btrfs, but it's advertised to be able to de-duplicate files.
In my application, I'd need to duplicate whole directory trees.
From what I learned, btrfs only de-duplicates in some post scan, not
immediately. Even just using
cp doesn't seem to trigger any
de-duplication (at least,
df shows an increased disk usage in the
size of the copied files).
Can I avoid moving data around altogether and tell
btrfs directly to
duplicate a file at another location, essentially just cloning its
In essence, similar to a hardlink, but with independent metadata (permissions, mod. times, ...).