On Thu, Apr 23, 2015 at 12:42 PM, Scott Preece <[email protected] > wrote:
> Hi, > Wanted to verify a few things and ask a couple of questions... > Chasing through the code a bit, it looks like Falcon stores information > about feed instances in a graph DB, using TinkerPop. The source of truth for instances are in Oozie DB. Only succeeded instances are stored in the graph db. > From the configs, it looks like TinkerPop is on top of BerkeleyJE. Is that > correct? Is it running as an in-memory database that gets loaded at startup > or as a persistent store that is queried as information is needed? > The backing store for titan graph db is by default configured to be berkeleydbje but is configurable to use HBase. > Is information about instances stored anywhere else? That is, when you use > the API to list he instances of a feed, does it get that information from > the graph DB? > This is gotten from Oozie. > What information does it store about an instance? scot, is the instance > represented as an object with a pre-defined structure or is it a graph node > to which properties are attached? > Latter. > Is any of this documented anywhere? Is this what the "Falcon config store > / Graph" in the Architecture diagram refers to? > The config store is different from graph store. Config store stores the user submitted entities. Graph store stores the lineage information and is static. > thanks,scott -- Regards, Venkatesh “Perfection (in design) is achieved not when there is nothing more to add, but rather when there is nothing more to take away.” - Antoine de Saint-Exupéry
