Hi all - I'm seeing this from a recent graph I built:

gremlin> :> g.V(4162).valueMap()
==>{source=[DS_106], sourceName=[GDELTRecord3]}
gremlin> :> g.V(4146).valueMap()
==>{source=[DS_106], sourceName=[GDELTRecord3]}
gremlin> :> g.V(4226).valueMap()
==>{source=[DS_106], sourceName=[GDELTRecord3]}
gremlin> :> g.V(4250).valueMap()
==>{source=[DS_106], sourceName=[GDELTRecord3]}
gremlin>
gremlin>
gremlin> :> g.V().has("source","DS_106")
==>v[4226]

The graph has an index on source like this:

PropertyKey sourceProperty = mgmt.makePropertyKey("source").dataType(String.class).cardinality(Cardinality.SINGLE).make();
JanusGraphIndex sourceIndex = mgmt.buildIndex("bySourceComposite", Vertex.class).addKey(sourceProperty).unique().buildCompositeIndex();
mgmt.setConsistency(sourceProperty, ConsistencyModifier.LOCK);
mgmt.setConsistency(sourceIndex, ConsistencyModifier.LOCK);

How could the graph end up with several vertices with the same source string?  Still learning graphs...

Thank you!

-Joe


--
This email has been checked for viruses by AVG.
https://www.avg.com

Hi Joe,

I just wanted to check a few things:

1. Did you happen to enable `storage.batch-loading`? See https://docs.janusgraph.org/operations/bulk-loading/#batch-loading

2. IIRC you are using Cassandra. Did you happen to change storage.cql.read-consistency-level + storage.cql.read-consistency-level?

I wouldn't be too surprised even if the answers to both questions are "no", because the locking approach heavily relies on the storage backend and Cassandra (at the moment) only offers eventual consistency.

Best,
Boxuan

Thank you Kevin and Boxuan for the help on this.  I was scratching my head on this and decided to blow away the graph and try again.  Every-time, I built a small graph and exported to graphML for viewing in Gephi I would have node IDs that only existed in the edges list.
I printed the nodeID in my code everywhere it was used, and I would never see it in the output, but the graphML had it in the edges list and those 'zombie nodes' did exist in the graph as confirmed by gremlin queries. This was happening because I was using:
VertexLabel sourceLabel = mgmt.makeVertexLabel("source").partition().make();

Once I removed partition, the "zombie" node IDs disappeared.  I wanted to use partition for that since those particular vertexes can have a lot of edges; potentially billions.  [https://docs.janusgraph.org/advanced-topics/partitioning/]

Perhaps I'm not using that correctly, or is this a bug?

-Joe

Hi Joe,

I just wanted to check a few things:

1. Did you happen to enable `storage.batch-loading`? See https://docs.janusgraph.org/operations/bulk-loading/#batch-loading

2. IIRC you are using Cassandra. Did you happen to change storage.cql.read-consistency-level + storage.cql.read-consistency-level?

I wouldn't be too surprised even if the answers to both questions are "no", because the locking approach heavily relies on the storage backend and Cassandra (at the moment) only offers eventual consistency.

Best,
Boxuan