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https://issues.apache.org/jira/browse/KAFKA-6822?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Matthias J. Sax resolved KAFKA-6822.
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Resolution: Abandoned
> Kafka Consumer 0.10.2.1 can not normally read data from Kafka 1.0.0
> -------------------------------------------------------------------
>
> Key: KAFKA-6822
> URL: https://issues.apache.org/jira/browse/KAFKA-6822
> Project: Kafka
> Issue Type: Bug
> Components: consumer, streams
> Reporter: Phil Mikhailov
> Priority: Major
>
> We have a microservices that use Kafka Streams which stuck in initialization
> of stream topolgy while filling StateStore from Kafka using KafkaConsumer.
> Microservice is build with Kafka Streams 0.10.2.1-cp1 (Confluent 3.2.1) but
> environment runs Kafka cluster 1.0.0 (Confluent 4.0.0).
> We reproduced this problem several times by restarting microservices and
> eventually had to reset the stream offsets to beginning in order unblock
> microservices.
> While investigating this problem more deeply we found out that StateStore
> (0.10.2.1) stuck in loading data using {{ProcessorStateManager}}. It uses
> KafkaConsumer (0.10.2.1) to fill the store and it calculates offsets like
> this:
> Fetcher:524
> {code:java}
> long nextOffset = partRecords.get(partRecords.size() - 1).offset() + 1;
> {code}
> Get the latest offset from records (which were got from {{poll}}) plus 1.
> So the next offset is estimated.
> In Kafka 1.0.0 otherwise broker explicitly provides the next offset to fetch:
> {code:java}
> long nextOffset = partitionRecords.nextFetchOffset;
> {code}
> It returns the actual next offset but not estimated.
> That said, we had a situation when StateStore (0.10.2.1) stuck in loading
> data. The reason was in {{ProcessorStateManager.restoreActiveState:245}}
> which kept spinning in consumer loop 'cause the following condition never
> happened:
> {code:java}
> } else if (restoreConsumer.position(storePartition) == endOffset) {
> break;
> }
> {code}
>
> We assume that consumer 0.10.2.1 estimates endoffset incorrectly in a case of
> compaction.
> Or there is inconsistency between offsets calculation between 0.10.2.1 and
> 1.0.0 which doesn't allow to use 0.10.2.1 consumer with 1.0.0 broker.
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