code: func (h *BindHandle) appendBindMeta(hash string, meta *BindMeta) {
  	newCache := h.bindInfo.Value.Load().(cache).copy()
  	newCache.removeStaleBindMetas(hash, meta)
  	newCache[hash] = append(newCache[hash], meta)
  	h.bindInfo.Value.Store(newCache)
  }
docs: // appendBindMeta addes the BindMeta to the cache, all the stale bindMetas are
  // removed from the cache after this operation.