Always reset agent connection backoff and enter fast sync when client…

… count < server count (kubernetes-sigs#632)

* Always reset backoff and enter fast sync when clien count < server count

* Only call ClientsCount() once

* Review comment

pkg/agent/clientset.go

@@ -183,9 +183,13 @@ func (cs *ClientSet) sync() {
  for {
  if err := cs.connectOnce(); err != nil {
  if dse, ok := err.(*DuplicateServerError); ok {
- klog.V(4).InfoS("duplicate server", "serverID", dse.ServerID, "serverCount", cs.serverCount, "clientsCount", cs.ClientsCount())
- if cs.serverCount != 0 && cs.ClientsCount() >= cs.serverCount {
+ clientsCount := cs.ClientsCount()
+ klog.V(4).InfoS("duplicate server", "serverID", dse.ServerID, "serverCount", cs.serverCount, "clientsCount", clientsCount)
+ if cs.serverCount != 0 && clientsCount >= cs.serverCount {
  duration = backoff.Step()
+ } else {
+ backoff = cs.resetBackoff()
+ duration = wait.Jitter(backoff.Duration, backoff.Jitter)
  }
  } else {
  klog.ErrorS(err, "cannot connect once")