code: func (sm *SyncManager) NewPeer(peer *peerpkg.Peer) {
  	// Ignore if we are shutting down.
  	if atomic.LoadInt32(&sm.shutdown) != 0 {
  		return
  	}
  	sm.msgChan <- &newPeerMsg{peer: peer}
  }
docs: // NewPeer informs the sync manager of a newly active peer.