Release Date: 25 March 2015

Neo4j 2.2 is a significant release, that provides read and write performance for massive operational throughput — making it our fastest and most scalable graph database yet.

Notably, this release includes:

  • A huge facelift to the Neo4j Browser, including many new ways to view and work with your data, including a new graph legend, the ability to terminate cypher queries, curving arrows, panning, visual query plans and much more.
  • A new cost based query planner for Cypher — which is much smarter at planning queries and more transparent about what it’s doing. This compiler is available in addition to the existing rule based compiler and Neo4j will automatically select which to use for each query (this behavior can be adjusted using compiler directives as described in the documentation of cypher query tuning).
  • Full support for profiling and explaining Cypher query plans, including a query plan visualizer in the Neo4j Browser.
  • Username and password authentication for accessing Neo4j. All access to the Neo4j Browser or REST APIs will now need to supply valid credentials. For more detail, see the section on server authentication and authorization in the documentation.
  • A new page cache, which is faster, provides significant improvements in handling of concurrent operations, and is easier to configure than the memory mapping in previous Neo4j releases — now requiring only a single configuration setting (see the configuration documentation for details).
  • Introduces fast-write buffering which dramatically increases the throughput of many write workloads without any configuration required.
  • The use of separate transactions logs for the graph and the indexes, co-ordinated by an XA system, has been replaced by a singular transactional management and one unified transaction log. This substantially reduces resource overhead and improves scalability. Note that as result of this, the previously exposed XA and JTA functionalities have been removed.
  • Many, many fixes improving stability, performance and usability.

All Neo4j users are recommended to upgrade to this release. Upgrading to Neo4j 2.2.0 requires a migration to the on-disk store and can not be reversed. Please ensure you have a valid backup before proceeding. Production users should note that there will be configuration changes required, and that applications will need to be updated to support authentication of database requests. Please see our Upgrading to Neo4j 2.2 FAQ for further details.

(Note: Neo4j 1.9 users may also upgrade directly to this release, and are recommended to do so carefully. We strongly encourage verifying the syntax and validating all responses from your Cypher scripts, REST calls, and Java code before upgrading any production system. For information about upgrading from Neo4j 1.9, please see our Upgrading to Neo4j 2 FAQ.)

For a full summary of changes in this release, please review the CHANGES.TXT file contained within the distribution.