code: func CheckStreamTimeoutLoop(ch <-chan *Lease) {
  	ticker := time.NewTicker(200 * time.Millisecond)
  	defer ticker.Stop()
  	array := make([]*Lease, 0, 1024)
  
  	for {
  		select {
  		case item, ok := <-ch:
  			if !ok {
  				// This channel close means goroutine should return.
  				return
  			}
  			array = append(array, item)
  		case now := <-ticker.C:
  			array = keepOnlyActive(array, now.UnixNano())
  		}
  	}
  }
docs: // CheckStreamTimeoutLoop runs periodically to check is there any stream request timeouted.
  // Lease is an object to track stream requests, call this function with "go CheckStreamTimeoutLoop()"