[
https://issues.apache.org/jira/browse/FLINK-2361?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14642489#comment-14642489
]
Andra Lungu commented on FLINK-2361:
------------------------------------
I get this one too...
"The interesting part is that in every superstep different vertices are
missing, even from those that were present in the previous superstep."
I tried a silly hack i.e. to remove all the edges containing the missing
vertex, but then another one would pop up...
-- And I sincerely think it's a Flink problem. I debugged that user code to the
bone... If it's the compacting hash table behind this, then we may be able to
kill two birds with one stone... That seems to be the problem in FLINK-2360 as
well...
> flatMap + distinct gives erroneous results for big data sets
> ------------------------------------------------------------
>
> Key: FLINK-2361
> URL: https://issues.apache.org/jira/browse/FLINK-2361
> Project: Flink
> Issue Type: Bug
> Components: Gelly
> Affects Versions: 0.10
> Reporter: Andra Lungu
>
> When running the simple Connected Components algorithm (currently in Gelly)
> on the twitter follower graph, with 1, 100 or 10000 iterations, I get the
> following error:
> Caused by: java.lang.Exception: Target vertex '657282846' does not exist!.
> at
> org.apache.flink.graph.spargel.VertexCentricIteration$VertexUpdateUdfSimpleVV.coGroup(VertexCentricIteration.java:300)
> at
> org.apache.flink.runtime.operators.CoGroupWithSolutionSetSecondDriver.run(CoGroupWithSolutionSetSecondDriver.java:220)
> at
> org.apache.flink.runtime.operators.RegularPactTask.run(RegularPactTask.java:496)
> at
> org.apache.flink.runtime.iterative.task.AbstractIterativePactTask.run(AbstractIterativePactTask.java:139)
> at
> org.apache.flink.runtime.iterative.task.IterationTailPactTask.run(IterationTailPactTask.java:107)
> at
> org.apache.flink.runtime.operators.RegularPactTask.invoke(RegularPactTask.java:362)
> at org.apache.flink.runtime.taskmanager.Task.run(Task.java:559)
> at java.lang.Thread.run(Thread.java:722)
> Now this is very bizzare as the DataSet of vertices is produced from the
> DataSet of edges... Which means there cannot be a an edge with an invalid
> target id... The method calls flatMap to isolate the src and trg ids and
> distinct to ensure their uniqueness.
> The algorithm works fine for smaller data sets...
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
