Index building parameters for HNSW
Parameter | Type | Default value | Description |
proxima.hnsw.builder.max_neighbor_count | uint32 | 100 | The maximum number of neighbors for a node in a graph. A larger value indicates a better connectivity of the graph. Correspondingly, the graph building cost and index size also increase. |
proxima.hnsw.builder.efconstruction | uint32 | 500 | The size of the neighboring area that can be scanned when a graph is being built. A larger value indicates a higher quality of the offline graph building but a lower index building speed. We recommend that you set the value to 400 for the first time. |
proxima.hnsw.builder.thread_count | uint32 | 0 | The number of threads that can be used. If you set the value of this parameter to 0, the number of threads that can be used is equal to the number of CPU cores of OpenSearch Vector Search Edition. |
Search parameter for HNSW
Parameter name | Type | Default value | Description |
proxima.hnsw.searcher.ef | uint32 | 500 | The number of the nearest neighbors that are scanned during an online search. A large value increases the retrieval ratio but slows down retrieval performance. We recommend that you set the value in the range of [100,1000]. |
proxima.hnsw.searcher.max_scan_ratio | float | None | The proportion of points that are scanned during an online search. A large value increases the retrieval ratio but slows down retrieval performance. |
proxima.hnsw.searcher.brute_force_threshold | uint32 | None | The minimum number of points that are scanned during an online search. If the value of this parameter exceeds the number of documents count in a shard, the search becomes brute force. |