transactional consistency (Was: LDAP Requirements comments)

To me, "transactional consistency" implies that an update
made by a client against a master (regardless of M/M v M/S)
is made available on all servers, in including the master
to which issued the request, simultaneously and atomically.

The current definition of multi-master implies that the
replication coordination is be done after client operation
is performed (completed) and this precluded "transactional
consistency".

I fully concur that supporting "transactional consistency",
for either M/M or M/S, is very difficult with the number
of replicas is greater than 2 (and is difficult when
equal to 2).

The definition, I hope, divorces the consistency model from
the replication model.


>So - I would prefer to keep the current definition of the Master Replica
>insofar as this aspect of the definition is concerned, because it
>explicitly encodes our operating assumption - that there is no requirement
>for communication with other master replicas before the write or
>update is performed.

I argue that this assumption will lead to an design which
precludes "transactional consistency".

I would prefer the definition be updated and the design be
allowed to preclude "transactional consistency".  As far
as the operating assumption, I see no reason to state that
there is no requirement for such communication.