Amazon OpenSearch k-NN

Category: SDKs & Libraries
Tags: vector-search, ann, managed-service, opensearch

Description

Amazon OpenSearch's k-NN plugin enables scalable and efficient vector search using approximate nearest neighbor (ANN) algorithms such as IVF and HNSW directly within a managed OpenSearch cluster. This is particularly useful for building, querying, and scaling vector databases on AWS.

Documentation & Source

Features

• Vector Search (k-NN): Implements k-nearest neighbors search to find the closest vectors to a query point in an index.
• Approximate k-NN (ANN) Algorithms: Supports efficient, scalable approximate search using algorithms like IVF and HNSW. Offers trade-offs between speed, accuracy, and resource usage.
• Exact k-NN Search: Provides brute-force search for exact nearest neighbors, with options for scoring scripts and Painless scripting extensions for custom distance functions.
• Multiple Distance Functions: Allows specification of the distance metric (space) for neighbor calculation.
• Automatic Backend Selection: Chooses the optimal engine and configuration based on selected mode and available memory.
• Sparse Vector Search (Neural Sparse Search): Supports efficient semantic search using sparse embedding models and inverted indexes, with options for automatic embedding generation or direct ingestion.
• Hybrid Search: Combines traditional keyword search with vector-based semantic search for improved relevance, using configurable search pipelines that can normalize and combine scores from multiple techniques.
• Customizable Search Pipelines: Enables post-filtering, aggregations, and complex query customizations within hybrid search workflows.
• Integration with AWS Managed OpenSearch: Directly usable within AWS managed OpenSearch clusters.
• Optimized for Large and Small Datasets: ANN methods for large datasets, exact search and custom scoring for smaller or filtered datasets, and flexible scripting for complex use cases.

Pricing

No pricing information is provided in the source content. For details about costs, refer to AWS OpenSearch managed service pricing.