Hi, > I was referring to problem a, which is about validators and other > commit hooks not being a part of the underlying MK-level merge > operation and thus for example not always catching things like > duplicate UUIDs being introduced or hard references being broken (i.e. > repository invariants that span more than one node). This issue also > affects the MongoMK implementation, though it's yet unclear how > important addressing it is in practice. For some deployments it may > well be a hard requirement.
this is what I tried to describe in http://jackrabbit.markmail.org/thread/5vh6bk7ei32jgtbg the MicroKernel only provides snapshot isolation, while a NodeStore implementation could also provide serializable snapshot isolation. as mentioned before, I think snapshot isolation is just fined because in most cases it is sufficient and allows for increased concurrency. for the cases where more consistency guarantees are needed, like unique UUIDs and hard references we should implement the validators accordingly and e.g. use a technique like materializing the conflict. regards marcel
