code: func NewManager() *Manager {
  	var lock sync.Mutex
  	return &Manager{
  		Logger:          defaultLogger,
  		SnapshotPeriod:  ManagerSnapshotPeriod,
  		CoalescePeriod:  ManagerCoalescePeriod,
  		QuiescentPeriod: ManagerQuiescentPeriod,
  		lock:            &lock,
  		cond:            sync.NewCond(&lock),
  		proxies:         make(map[string]Proxy),
  	}
  }
docs: // NewManager initializes a Manager. After initialization, the exported
  // fields should be configured as desired. To start the Manager, execute
  // Run in a goroutine.