[jira] [Commented] (KAFKA-7725) Add a delay for further CG rebalances, beyond KIP-134 group.initial.rebalance.delay.ms

["Boyang Chen (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/KAFKA-7725?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16730800#comment-16730800 ] 

Boyang Chen commented on KAFKA-7725:
------------------------------------

Thanks [~astubbs] for sharing this issue. Will add this to the KIP-345 Jira list.

> Add a delay for further CG rebalances, beyond KIP-134 group.initial.rebalance.delay.ms
> --------------------------------------------------------------------------------------
>
>                 Key: KAFKA-7725
>                 URL: https://issues.apache.org/jira/browse/KAFKA-7725
>             Project: Kafka
>          Issue Type: New Feature
>          Components: clients, consumer, core
>    Affects Versions: 2.1.0
>            Reporter: Antony Stubbs
>            Priority: Major
>
> KIP-134 group.initial.rebalance.delay.ms was a good start, but there are much bigger problems where after a system is up and running, consumers can leave and join in large amounts, causing rebalance storms. One example is Mesosphere deploying new versions of an app - say there are 10 instances, then 10 more instances are deployed with the new version, then the old 10 are scaled down. Ideally this would be 1 or 2 rebalances, instead of 20.
> The trade off is that if the delay is 5 seconds, every consumer joining within that window would extend it by another 5 seconds, potentially causing partitions to never be processed. To mitigate this, either a max rebalance delay could also be added, or multiple consumers joining won't extend the rebalance delay, so that it's always a max of 5 seconds.
> Related: [KIP-345: Introduce static membership protocol to reduce consumer rebalances|https://cwiki.apache.org/confluence/display/KAFKA/KIP-345%3A+Introduce+static+membership+protocol+to+reduce+consumer+rebalances]
> KAFKA-7018: persist memberId for consumer restart



--
This message was sent by Atlassian JIRA
(v7.6.3#76005)