Module hnsw 

HNSW (Hierarchical Navigable Small World) Index

Table of Contents

• HnswIndex: Main HNSW graph structure for ANN search
• HnswNode: Node in the HNSW graph with multi-layer connections
• HnswConfig: Configuration parameters (M, ef_construction, ef_search)
• Search Algorithm: Greedy beam search with layer traversal

Algorithm Overview

HNSW builds a multi-layer graph where:

• Higher layers have fewer nodes (exponential decay)
• Each node connects to M neighbors per layer
• Search starts from top layer, greedily descends
• Bottom layer search uses beam width ef_search for recall

Structs

HnswIndex

HNSW Index for approximate nearest neighbor search

HnswNode

HNSW node representing a vector in the graph

HnswStats

HNSW index statistics