OpenSearchCon India 2026

Search engines are widely used but rarely understood at a deeper level. What actually happens between the moment a user submits a query and the results appear on the screen?
This session provides a technical deep dive into the OpenSearch query execution pipeline, exploring how user queries are processed, distributed, and ranked across a cluster. The talk begins with how text is analyzed and indexed using Lucene, including tokenization, analyzers, and inverted indexes. It then walks through how queries are parsed, executed across shards, and scored using relevance algorithms such as BM25.
Participants will also learn how OpenSearch coordinates distributed search, merges shard results, and optimizes performance through caching and query planning. Finally, we will examine debugging tools and profiling techniques that help developers understand and tune search relevance and performance.
By the end of the session, attendees will have a deeper understanding of the internals of OpenSearch and how those internals influence search quality and system performance.