I'm a little confused by the user guide, it said that
autoDataGravitation - Whether data gravitation occurs for every cache miss. By default this is set to false to prevent unnecessary network calls. Most use cases will know when it may need to gravitate data and will pass in an Option to enable data gravitation on a per-invocation basis. If autoDataGravitation is true this Option is unnecessary.
But do we have any chance to know if the cache miss is caused by server failure or the data is not loaded before in the server?