Improve vertex label lookup

[mad]

Fix for #1709 Signed-off-by: Pavel Ershov [email protected]

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[mad]

Root cause is it added relations container

We use multiples EventListener in our traversal that do some work on newly added/changed vertices. When we add multuple vertices with properties and trying to access to label in same tx from listeners it lead to sequntial scan added relations container this apect is inefficient.

Test JanusGraphPerformanceMemoryTest.labelRetrivial demonstrte this case, 5s on master vs 0,5s on this branch

We see same issue when we want to rewrite properties in same tx. Rewrite properties required remove from added relation container is it sequntial scan operations, see https://github.com/JanusGraph/janusgraph/pull/1701

For avoid this issues we may avoid this pattern of use OR add label cache, use more complex structure for added relations container

[mad]

I think current approach may be simplified, for avoid redundant operation we need use SimpleVertexQueryProcessor for this label query. I will try this and test

And remove new field from AbstractVertex that increase vertex size to 8 byte

[linux-foundation-easycla[bot]]

The committers are authorized under a signed CLA.

• :white_check_mark: Pavel (079e09c70bf38869351d998ec6e9b7fd0cf3fa72)

[mad]

Current approach introduced new field to AbstractVerex, so vertex size is increased. I don't think it will good for some use cases.

Need more investigation. May be some query cache will help with this type of issue https://github.com/JanusGraph/janusgraph/blob/master/janusgraph-core/src/main/java/org/janusgraph/graphdb/database/StandardJanusGraph.java#L306

[li-boxuan]

@mad Is this ready for review? If so, can you rebase it? Otherwise, we can convert it to a draft.