On 10/02/2009, at 10:30 AM, Paul Davis wrote:
Compaction and revision stemming (which is required to avoid
unbounded
growth) make intermediate states inconsistent because they can
delete either
the data of a document rev or the document rev itself. In the face of
compaction, it's possible for consistency to only be achieved when
the
replication reaches the same MVCC commit point that the compaction
was
operating against. Revision stemming has a similar effect, although
it has
the further issue of being automatic i.e. not scheduled.
That's ignoring replication failure, either temporary or permanent,
which
further complicates the picture. Given that intermediate states are
not
necessarily consistent, anything that leaves you in an intermediate
state
without a way forward, repudiates the guarantee of Eventual
Consistency.
I'm pretty sure the rest of this is wrong though.
I mean no offense, but I'm looking for something more than 'pretty
sure'. I'm trying to work through these issues so that I understand
the formal model and design intention completely and properly.
Antony Blakey
-------------
CTO, Linkuistics Pty Ltd
Ph: 0438 840 787
Borrow money from pessimists - they don't expect it back.
-- Steven Wright
