JanusGraph/janusgraph

values().profile() much slower than valueMap().profile() when `query.batch` is disabled

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#2,185 opened on Aug 16, 2020

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 (4 comments) (0 reactions) (0 assignees)Java (1,137 forks)batch import
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Description

graph = JanusGraphFactory.open("inmemory")
g = graph.traversal()
for (i = 0; i < 100; i++) {
g.addV().property("prop", "value").iterate();
}
g.V().valueMap().profile()
g.V().values().profile()

Tested on 0.6.0 SNAPSHOT version. image image

caused by https://github.com/JanusGraph/janusgraph/blob/6b6371d6f18ebf1d32c68254e87d238bb7528869/janusgraph-core/src/main/java/org/janusgraph/graphdb/tinkerpop/optimize/JanusGraphLocalQueryOptimizerStrategy.java#L108-L110

Contributor guide

Research direction
Inspect the referenced code at JanusGraphLocalQueryOptimizerStrategy.java lines 108-110 and understand why values() is slower than valueMap() when query.batch is disabled. Consider optimizing the query optimizer strategy to avoid unnecessary overhead.
Tech stack
java
Domain
backenddatabase
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
JavaJanusGraph basics
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
70