hi, If the goal is simply to collect the rebalance timing, using a broker-side plugin feels a bit overkill. Alternatively, could we just expose the assignmentTimestamp via the DescribeGroupsResponse? With this new field, users could set up a cron job or monitor to poll the timestamp periodically. While it might not cover 100% of real-time event tracking use cases, it is much simpler and poses a significantly lower risk to the server.
Best, Chia-Ping On 2026/04/04 07:44:29 jian fu wrote: > Hi everyone, > > I would like to start a discussion for this small KIP. > > https://cwiki.apache.org/confluence/x/UZc8G > > Rebalance is the most important consumer event, and Kafka is moving toward > server-side rebalance. > > Today, client-side/sdk callbacks are useful but not always reliable > operationally (SDK dependency, Not easy for central management). In > incidents, key rebalance evidence is often missing on the client side.On > the broker side, logs and metrics are still limited for automation: logs > are hard to integrate reliably, and metrics do not include the most > actionable key (group.id). > > This KIP proposes a lightweight broker-side callback to expose key > rebalance context (including group.id) for centralized observability and > automation, without forcing client upgrades and without adding > high-cardinality metric tags. > > Your feedback is greatly appreciated. Thank you! > > Regards > Jian >
