anchor.diff:  |ha.cluster_server |ha.host.coordination
   |ha.server |ha.host.data
   |=========================================================
  +
  +
  +Upgrading for Providers
  +~~~~~~~~~~~~~~~~~~~~~~~
  +
  +IMPORTANT: It is recommended that providers also review all the upgrade instructions specified for users. Many of the
  +changes there may prove important for the provider's implementation.
  +
  +Graph Database Providers
  +^^^^^^^^^^^^^^^^^^^^^^^^
  +
  +IO Version Check
  +++++++++++++++++
  +
  +In the `Graph.io()` method, providers are to bootstrap the `Io` instance returned with their own custom serializers
  +typically provided through a custom `IoRegistry` instance. Prior to this change it was not possible to easily determine
  +the version of `Io` that was expected (nor was it especially necessary as TinkerPop didn't have breaking format changes
  +between versions). As of 3.3.0 however, there could be IO test incompatibilities for some providers who need to
  +register a different `IoRegistry` instance depending on the version the user wants.
  +
  +To allow for that check, the `Io` interface now has the following method:
  +
  +[source,java]
  +----
  +public <V> boolean requiresVersion(final V version);
  +----
  +
  +which allows the graph provider to check if a specific `GryoVersion` or `GraphSONVersion` is required. Using that
  +information, the provider could then assign the right `IoRegistry` to match that.
  +
  +See: link:https://issues.apache.org/jira/browse/TINKERPOP-1767[TINKERPOP-1767]
   
   
   TinkerPop 3.3.0
  
positive.code: 
  In particular, these properties referenced in TinkerPop documentation and configuration were renamed:
  
  |=========================================================
  |old (2.3) |new (3.3)
  |node_auto_indexing |dbms.auto_index.nodes.enabled
  
negative.code: some key defaults were missed. Specifically, calls to `Graph.io(graphson())` and `Graph.io(gryo())` were still using
  the old versions. The defaults have now been changed to ensure 3.0 is properly referenced in those cases.
  
  Upgrade Neo4j
  ^^^^^^^^^^^^^
  
  