jackrabbit-oak-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Marcel Reutegger <mreut...@adobe.com>
Subject RE: SegmentNodeStore merge operations
Date Thu, 07 Mar 2013 11:08:14 GMT

> 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.


View raw message