Hi,
When configuring flow control quota for users and clients, Kafka will add a child node to /config/users or /config/clients in zookeeper. When deleting a flow control quota config, the existing node in zookeeper will not be deleted even if the configs in the node are empty. So if a client repeatedly configure and delete flow control quota for different users and clients, the node in zookeeper will increase continuously, which may leads to severe problems such as memory leak. I suggest that we can delete the node in zookeeper (child nodes under /config/users and /config/clients) if the configs in the node are empty. Thanks, -- Junyang Liu