[
https://issues.apache.org/jira/browse/FLINK-9349?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16486697#comment-16486697
]
ASF GitHub Bot commented on FLINK-9349:
---------------------------------------
Github user tzulitai commented on a diff in the pull request:
https://github.com/apache/flink/pull/6040#discussion_r190111529
--- Diff:
flink-connectors/flink-connector-kafka-base/src/test/java/org/apache/flink/streaming/connectors/kafka/internals/AbstractFetcherTest.java
---
@@ -416,9 +520,16 @@ protected TestFetcher(
false);
}
+ /**
+ * Emulation of partition's iteration which is required for
+ * {@link
AbstractFetcherTest#testConcurrentPartitionsDiscoveryAndLoopFetching}.
+ * @throws Exception
+ */
@Override
public void runFetchLoop() throws Exception {
- throw new UnsupportedOperationException();
+ for (KafkaTopicPartitionState ignored:
subscribedPartitionStates()) {
+ Thread.sleep(10L);
--- End diff --
This would only let the test fail "occasionally", right?
I would like this to be changed, so that we always have the test failing
without the copy on write fix.
We could do this by having a dummy source context that blocks on record
emit.
> KafkaConnector Exception while fetching from multiple kafka topics
> -------------------------------------------------------------------
>
> Key: FLINK-9349
> URL: https://issues.apache.org/jira/browse/FLINK-9349
> Project: Flink
> Issue Type: Bug
> Components: Kafka Connector
> Affects Versions: 1.4.0, 1.5.0
> Reporter: Vishal Santoshi
> Assignee: Sergey Nuyanzin
> Priority: Critical
> Attachments: Flink9349Test.java
>
>
> ./flink-connectors/flink-connector-kafka-0.9/src/main/java/org/apache/flink/streaming/connectors/kafka/internal/Kafka09Fetcher.java
>
> It seems the List subscribedPartitionStates was being modified when
> runFetchLoop iterated the List.
> This can happen if, e.g., FlinkKafkaConsumer runs the following code
> concurrently:
> kafkaFetcher.addDiscoveredPartitions(discoveredPartitions);
>
> {code:java}
> java.util.ConcurrentModificationException
> at
> java.util.LinkedList$ListItr.checkForComodification(LinkedList.java:966)
> at java.util.LinkedList$ListItr.next(LinkedList.java:888)
> at
> org.apache.flink.streaming.connectors.kafka.internal.Kafka09Fetcher.runFetchLoop(Kafka09Fetcher.java:134)
> {code}
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
