[jira] [Commented] (FLINK-24542) Expose the freshness metrics for kafka connector

["Qingsheng Ren (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/FLINK-24542?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17430043#comment-17430043 ] 

Qingsheng Ren commented on FLINK-24542:
---------------------------------------

Thanks [~zlzhang0122] I checked [the documentation of Kafka|https://kafka.apache.org/documentation/#consumer_monitoring] but didn't find the metric "freshness". According to the blog post I assume this is a derived metric instead of a standard metric exposed by Kafka client. I think using other tools like Burrow to monitor Kafka in the bypass would be a better choice.

> Expose the freshness metrics for kafka connector
> ------------------------------------------------
>
>                 Key: FLINK-24542
>                 URL: https://issues.apache.org/jira/browse/FLINK-24542
>             Project: Flink
>          Issue Type: Improvement
>          Components: Connectors / Kafka
>    Affects Versions: 1.12.2, 1.14.0, 1.13.1
>            Reporter: zlzhang0122
>            Priority: Major
>             Fix For: 1.15.0
>
>
> When we start a flink job to consume apache kafka, we usually use offsetLag, which can be calulated by current-offsets minus committed-offsets, but sometimes the offsetLag is hard to understand, we can hardly to judge wether the value is normal or not. Kafka have proposed a new metric: freshness(see [a-guide-to-kafka-consumer-freshness|https://www.jesseyates.com/2019/11/04/kafka-consumer-freshness-a-guide.html?trk=article_share_wechat&from=timeline&isappinstalled=0]).
> So we can also expose the freshness metric for kafka connector to improve the user experience.From this freshness metric, user can easily know wether the kafka message is backlog and need to deal with it.



--
This message was sent by Atlassian Jira
(v8.3.4#803005)