The current lease renewal code in DFSClient gives up after several retries, if the soft limit exceeds. This causes the client to abort. Without this self destruction behavior, lease renewal can be retried infinitely due to unrelated low-level issue and prevent DFSClient and associated Connection from getting garbage collected.
However, giving up at passage of the soft limit has been shown to be too fragile; A long GC on namenode or transient network outage can make clients fail. We need the self-destruct behavior, but clients should be allowed to retry for longer period of time.