Is there some "high level" overview of Lizard/Mantis/TDB2 yet extant? Like the kind of thing we might see at a conference?
In any event, thanks for working on this-- it's great to know that Jena will be able to cluster soon. --- A. Soroka The University of Virginia Library On Jun 8, 2015, at 1:24 PM, Andy Seaborne <[email protected]> wrote: > On 08/06/15 17:48, Marco Neumann wrote: >> is TDB2 going to replace TDB or is TDB2 a new cluster product? > > Whatever people (users, developers) want. Migrating Dbs is not as easy as > ungrading code. Running oaj.tdb and oaj.tdb2 side by side > > (TDB2 is itself 7 maven modules ATM - some can be combined as they are small > and just "a good idea at the time"). > > TDB2 is not the cluster (that's Lizard). Mantis started as the separation > out of the low level code needed for Lizard. Initially validation of the > reworking of transaction and datastructures, a little extra work has made it > as viable as "TDB2" > > Andy > > (oaj = org.apache.jena) > >> >> Marco >> >> On Mon, Jun 8, 2015 at 11:41 AM, Andy Seaborne <[email protected]> wrote: >>> Informational announcement: TDB2 >>> >>> TDB2 is a reworking of TDB based on updated implementations of transactions >>> and transactional data structures for project Lizard (a clustered SPARQL >>> store). >>> >>> TDB2 has: >>> >>> * Arbitrary scale write-once transactions >>> * New transaction system - can add other first class components. >>> (e.g. text indexes, cache tables) >>> * Models works across transaction boundaries >>> * Cleaner, simpler, more maintainable >>> >>> TDB2 databases are not compatible with TDB databases. It uses a more >>> efficient encoding for RDF terms. [1] >>> >>> Being a database, the new indexing and transaction code needs time to settle >>> to bring the maturity up. I'm using that tech in Lizard development. >>> >>> Andy >>> >>> TDB2 code: >>> https://github.com/afs/mantis/tree/master/tdb2 >>> >>> Lizard slides: >>> http://www.slideshare.net/andyseaborne/201411-apache-coneu-lizard >>> >>> >>> [1] An upgrade path using TDB1-style encoding is possible; it is an one-way >>> upgrade path and not reversible [2]. TDB2 adds control files for the >>> copy-on-write data structures that TDB1 does not understand. >>> >>> [2] Actually, if the encoding is compatible, what will happen is that TDB1 >>> will see the database at the time of the upgrade. Welcome to copy-on-write >>> immutable data structures. >> >> >> >
