Title: Apache Lucene™ 9.1.0 available category: core/news URL: save_as:

The Lucene PMC is pleased to announce the release of Apache Lucene 9.1.0.

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 9.1.0 Release Highlights:

New features

• Lucene JARs are now proper Java modules, with module descriptors and dependency information
• Support for filtering in nearest-neighbor vector search
• Support for intervals queries in the standard query syntax
• A new token filter SpanishPluralStemFilter for precise stemming of Spanish plurals

Optimizations

• Up to 30% improvement in index throughput for high-dimensional vectors
• Up to 10% faster nearest neighbor searches on high-dimensional vectors
• Faster execution of “count” searches across different query types
• Faster counting for taxonomy facets
• Several other search speed-ups, including improvements to PointRangeQuery, MultiRangeQuery, and CoveringRangeQuery

Other

• The test framework is now a module, so all classes have been moved from to org.apache.lucene.tests.* to avoid package name conflicts
• Lucene now faithfully implements the HNSW algorithm for nearest neighbor search by supporting multiple graph layers

… plus a number of helpful bug fixes!

Please read CHANGES.txt for a full list of new features and changes:

https://lucene.apache.org/core/9_1_0/changes/Changes.html