Simon Cooper

Principal Software Engineer I

Author’s articles

HNSW graph: How to improve Elasticsearch performance

Basics

September 29, 2025

HNSW graph: How to improve Elasticsearch performance

Learn how to use the HNSW graph M and ef_construction parameters to improve search performance.

By: Simon Cooper

Vector Database

August 8, 2025

Using Direct IO for vector searches

Using rescoring for kNN vector searches improves search recall, but can increase latency. Learn how to reduce this impact by leveraging direct IO.

By: Simon Cooper

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