[KAFKA-9583] OffsetsForLeaderEpoch requests are sometimes not sent to the leader of partition

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.4.0, 2.3.1
• Fix Version/s: 2.6.0, 2.5.1
• Component/s: clients
• Labels: newbie patch pull-request-available
• Flags: Patch
• External issue URL: https://github.com/apache/kafka/pull/8077
• Assignee: Unassigned
• Reporter: Andy Fang
• Created: 20/Feb/20 22:52
• Updated: 09/Apr/20 21:07
• Resolved: 09/Apr/20 21:07

Description

In validateOffsetsAsync, we group the requests by leader node for efficiency. The list of topic-partitions are grouped from partitionsToValidate (all partitions) to node => fetchPostitions (partitions by node).

However, when actually sending the request with OffsetsForLeaderEpochClient, we use partitionsToValidate, which is the list of all topic-partitions passed into validateOffsetsAsync. This results in extra partitions being included in the request sent to brokers that are potentially not the leader for those partitions.

I have submitted a PR, https://github.com/apache/kafka/pull/8077, that fixes this issue.

Issue Links

• links to: GitHub Pull Request #8077