THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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Ideally, consumer offsets stored in the __consumer_offsets topic would be associated with the topic ID for which they were read. However, given the way the __consumer_offsets is compacted, this may be difficult to achieve in a forwards compatible way. This change will be left until topic IDs are implemented in the clients.
Group Metadata Manager
Another future improvement opportunity is to use topicId in GroupMetadataManager.offsetCommitKey in the offset_commit topic. This may save some space.
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