Title: Apache Luceneā¢ 9.0.0 available category: core/news URL: save_as:
The Lucene PMC is pleased to announce the release of Apache Lucene 9.0.0.
Apache Lucene is a high-performance, full-featured search engine library written entirely in Java. It is a technology suitable for nearly any application that requires structured search, full-text search, faceting, nearest-neighbor search across high-dimensionality vectors, spell correction or query suggestions.
This release contains numerous bug fixes, optimizations, and improvements, some of which are highlighted below. The release is available for immediate download at:
https://lucene.apache.org/core/downloads.html
Lucene 9.0.0 Release Highlights:
System requirements
- Lucene 9.0 requires JDK 11 or newer
New features
- Support for indexing high-dimensionality numeric vectors to perform nearest-neighbor search, using the Hierarchical Navigable Small World graph algorithm
- New Analyzers for Serbian, Nepali, and Tamil languages
- IME-friendly autosuggest for Japanese
- Snowball 2, adding Hindi, Indonesian, Nepali, Serbian, Tamil, and Yiddish stemmers
- New normalization/stemming for Swedish and Norwegian
Optimizations
- Up to 400% faster taxonomy faceting
- 10-15% faster indexing of multi-dimensional points
- Several times faster sorting on fields that are indexed with points. This optimization used to be an opt-in in late 8.x releases and is now opt-out as of 9.0.
- ConcurrentMergeScheduler now assumes fast I/O, likely improving indexing speed in case where heuristics would incorrectly detect whether the system had modern I/O or not
- Encoding of postings lists changed from FOR-delta to PFOR-delta to save further disk space
Other
- File formats have all been changed from big-endian order to little endian order
- Lucene 9 no longer has split packages. This required renaming some packages outside of the lucene-core JAR, so you will need to adjust some imports accordingly.
- Using Lucene 9 with the module system should be considered experimental. We expect to make progress on this in future 9.x releases.
Please read CHANGES.txt for a full list of new features and changes:
https://lucene.apache.org/core/9_0_0/changes/Changes.html