Tzu-Li (Gordon) Tai created FLINK-8410:
------------------------------------------
Summary: Kafka consumer's commitedOffsets gauge metric is
prematurely set
Key: FLINK-8410
URL: https://issues.apache.org/jira/browse/FLINK-8410
Project: Flink
Issue Type: Bug
Components: Kafka Connector, Metrics
Affects Versions: 1.3.2, 1.4.0, 1.5.0
Reporter: Tzu-Li (Gordon) Tai
Assignee: Tzu-Li (Gordon) Tai
Fix For: 1.3.3, 1.5.0, 1.4.1
The {{committedOffset}} metric gauge value is set too early. It is set here:
https://github.com/apache/flink/blob/master/flink-connectors/flink-connector-kafka-0.9/src/main/java/org/apache/flink/streaming/connectors/kafka/internal/Kafka09Fetcher.java#L236
This sets the committed offset before the actual commit happens, which varies
depending on whether the commit mode is auto periodically, or committed on
checkpoints. Moreover, in the 0.9+ consumers, the {{KafkaConsumerThread}} may
choose to supersede some commit attempts if the commit takes longer than the
commit interval.
While the committed offset back to Kafka is not a critical value used by the
consumer, it will be best to have more accurate values as a Flink-shipped
metric.
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
