Release Notes: Neo4j 1.9

Release Date: 13 May 2013

The 1.9 release of Neo4j builds upon the previous 1.8 releases and brings extensive improvements in stability and performance. In addition, Neo4j 1.9 Enterprise introduces auto-clustering support, with dramatically simplified configuration and deployment for high demand production use.

• Support for auto-clustering in Neo4j Enterprise, which replaces the previous Zookeeper based HA clustering, provides a streamlined deployment process and is much safer and more resilient in failure scenarios.
• New neo4j-arbiter tool, which acts as a voting instance in a Neo4j cluster but does not keep a data store or handle transactions.
• Addition of string manipulation, timestamp and other functions to the Cypher query language.
• Improvements to memory utilization, which reduces working memory requirements and improves overall performance.
• New REST endpoints for inspecting cluster status information (master, slave, etc).
• Correction of several concurrency and performance issues.
• Improvements to Online Backup in Neo4j Enterprise, including auto-detection of full vs incremental backup based on existing content at the backup location.
• Updates to Neo4j server webadmin, including welcome pages for new users.

It is recommended to upgrade all previous Neo4j installations to this release. Neo4j 1.9 does not require any explicit upgrade to persistent stores created using Neo4j 1.7 and 1.8 installations, however current users of Neo4j Enterprise must consult the documentation and update the cluster configuration. Please see the deployment and cluster upgrade sections of the neo4j manual for more detail. Also note that Neo4j 1.9 is tested and supported with Oracle JRE 7. Users of previous Java versions should upgrade to Oracle JRE 7 when deploying Neo4j 1.9. For a full summary of changes in this release, please review the CHANGES.TXT file contained within the distribution. As part of the Neo4j 1.9 release, multiple behaviours and features of Neo4j have been declared as deprecated, in order to help users prepare for the removal of these in the next major Neo4j release. A list of deprecations can be found in the Neo4j manual.