0.19.0.RC1 is out. You can download it here. It is a major release candidate release of elasticsearch.
This is the first time we release a “release candidate” for elasticsearch. The aim is to get users to try it out, fix any problems found with it, and release a final
0.19.0 release as soon as possible.
Major features include improved indexing performance, more control over shard allocation, more statistics and simpler API for stats, an update API that accepts a script to perform an update on a document, better state storage when using local gateway, and many bug fixes.
This release requires a full cluster restart in order to upgrade to the new version (including issuing a flush across all indices before the restart). If you are using the (default) local gateway, it will automatically be upgraded to a new and improved state format (with backups of the original state).
The structure of the project has also changed, moving all the plugins to their own repos under github. Installing a plugin now requires specifying the location and version to install it from.