11 replies

LazyBarrierStrategy/NoOpBarrierStep incompatible with path-tracking

Hi all!

In this JanusGraph post (TreeStep and MultiQuery support), we were investigating if

TreeStep

TreeStep

could be used jointly with bulked traversers so as to improve traversal time.

Based on answers there, it looks like TinkerPop's

LazyBarrierStrategy

LazyBarrierStrategy

explicitly excludes "path-tracking" traversals (https://github.com/apache/tinkerpop/blob/master/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/strategy/optimization/LazyBarrierStrategy.java#L85) and won't insert

NoOpBarrierStep

NoOpBarrierStep

s in those cases, preventing us from bulking traversers.

At a high level, I imagine this could be needed if traversers history was lost on bulking. Though, I'm not familiar enough with the code to be able to tell if this could concretely be a reason.

I have observed some "path-tracking" traversals (with

TreeStep

TreeStep

) to run properly with bulking on JanusGraph (TreeStep and MultiQuery support). In addition, commenting out the check on

TraverserRequirement.PATH

TraverserRequirement.PATH

(https://github.com/apache/tinkerpop/blob/master/gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/strategy/optimization/LazyBarrierStrategy.java#L85) does not break

gremlin-core

gremlin-core

unit tests locally.

So my question is: would anyone have context on why "path-tracking" traversals can't use bulking? Is there any chance this exclusion could be scoped down to a subset of "path-tracking" traversals maybe?

Any pointer appreciated!

LazyBarrierStrategy/NoOpBarrierStep incompatible with path-tracking

LazyBarrierStrategy/NoOpBarrierStep incompatible with path-tracking

Similar Threads

Similar Threads

Similar Threads