On Wed, Mar 25, 2020 at 09:45:39AM +0000, Johannes Thumshirn wrote:

Can you please elaborate on that? Why doesn't this hold true for a 
normal file system? If we split the DIO write into multiple BIOs with 
zone-append, there is nothing which guarantees the order of the written 
data (at least as far as I can see).

Of course nothing gurantees the order.  But the whole point is that the
order does not matter.