Before Creating the Enhancement Request
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