Before Creating the Enhancement Request

• I have confirmed that this should be classified as an enhancement rather than a bug/feature.

Summary

Skip unnecessary RPC when topic has no message queues.

Motivation

In the current rebalance process, an RPC to get consumer IDs is triggered even if the topic's mqSet is empty. Allocation occurs only when both the mqSet and the returned consumerId list are non-empty, so this RPC is redundant when the mqSet is empty.

Describe the Solution You'd Like

Skip unnecessary RPC when topic has no message queues.

Describe Alternatives You've Considered

No

Additional Context

No response