OpenSearchCon Europe 2026

Lucene Vector Search Update

There have been a lot of exciting developments in Lucene's vector search implementation recently: so many it's hard to keep track. This talk will survey all the many contributions that have come in over the last year or two, give examples of how to make use the new capabilities, and point the way for future work in this area.

Some of the specific topics may include:

* seeded search (start graph walk from a known point)
* optimistic search (safe pro-rating for efficient multi-segment search)
* Acorn-based search (more efficient application of filters)
* advances in quantization
* efficient indexing using binary partitioning over vector fields
* more efficient merging: finally, we can re-use information from graphs in existing segments and don't have to start from scratch
* proposed integrations: FAISS, CUVS, DiskANN

We'll dive more deeply into some selected topics, but the general idea is to convey the breadth of activity and the diversity of contributors.