[KAFKA-14797] MM2 does not emit offset syncs when conservative translation logic exceeds positive max.offset.lag

• Type: Bug
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Fix Version/s: 3.5.0, 3.4.1, 3.3.3
• Component/s: mirrormaker
• Assignee: Greg Harris
• Reporter: Greg Harris
• Created: 08/Mar/23 23:05
• Updated: 21/Mar/23 13:51
• Resolved: 21/Mar/23 13:51

Description

This is a regression in MirrorMaker 2 introduced by KAFKA-12468.

Reproduction steps:
1. Set max.offset.lag to a non-zero value.
2. Set up a 1-1 replication flow which does not skip upstream offsets or have a concurrent producer to the target topic.
3. Produce more than max.offset.lag records to the source topic and allow replication to proceed.
4. Examine end offsets, checkpoints and/or target consumer group lag

Expected behavior:
Consumer group lag should be at most max.offset.lag.

Actual behavior:
Consumer group lag is significantly larger than max.offset.lag.

Issue Links

• is caused by: KAFKA-12468 Initial offsets are copied from source to target cluster
• links to: GitHub Pull Request #13367