ASYNC_WAL and visibility

[Viacheslav Krot <kr...@gmail.com>]

Hi all,
I cannot find any good information about ASYNC_WAL semantics.
As much as I understand the worst I can get - data loss in case of region
failure.
But the question I have - can it affect visibility in any way? Does it
still follow the principle "When a client receives a "success" response for
any mutation, that mutation is immediately visible to both that client and
any client with whom it later communicates through side channels" ?
Another question - is data loss possible in any situation other than region
failure?