On 2019-02-15 1:38 p.m., Chris Murphy wrote:
>
> Well I'd say maybe use -vvv and --no-data instead of -f and see what
> it's doing. It sounds like the former has no payload, just difference
> information, and the latter has a payload. I don't know why.
> 
> 


Both have all the payload they need to re-create the subvolumes.  The
first one correctly CoW's the file from subvolume a.. the second one
stuffs it in the output... Why is indeed the question.