THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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InvokeConsumerRebalance (introduced above) will trigger one rebalance immediately on static membership, which is mainly used for fast scale down/host replacement cases (we detect consumer failure faster than the session timeout). This API will send a request a ConsumerRebalanceRequest to group coordinator, and the coordinator will decide whether to take this metadata change request based on its status at time.
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