Chris Hegarty

Chris Hegarty

Principal Software Engineer II

Chris is a committer and PMC member on the Apache Lucene Project, as well as a committer and reviewer in OpenJDK.

Articles by Chris Hegarty

A simdvec deep-dive: How Elasticsearch uses neural-net and video-codec CPU instructions for vector search

Four ways Elasticsearch's vector search engine reuses neural-network, video-codec and cryptography CPU instructions for up to 6x speedups; with the math, the failed attempts and the benchmarks.

Lorenzo Dematte

Elasticsearch simdvec deep-dive: Walking the memory tightrope to 2x better vector throughput

A deep dive into four optimizations (cascade unrolling, batch prefetching, dim-axis unrolling, a structural refactor) that pushed Elasticsearch simdvec to 2x vector throughput by working with the CPU, not against it.

Lorenzo Dematte

How we doubled vector search throughput on Elasticsearch Serverless

How we brought Elasticsearch's native SIMD scoring engine to serverless, and why serverless is where vector search innovation happens next.

Chris Hegarty

How we built Elasticsearch simdvec to make vector search one of the fastest in the world

How we built Elasticsearch simdvec, the hand-tuned SIMD kernel library behind every vector search query in Elasticsearch.

Chris Hegarty

Apache Lucene 2025 wrap-up

2025 was a stellar year for Apache Lucene; here are our highlights.

Benjamin Trent

Faster ES|QL stats with Swiss-style hash tables

How Swiss-inspired hashing and SIMD-friendly design deliver consistent, measurable speedups in Elasticsearch Query Language (ES|QL).

Chris Hegarty

Up to 12x Faster Vector Indexing in Elasticsearch with NVIDIA cuVS: GPU-acceleration Chapter 2

Discover how Elasticsearch achieves nearly 12x higher indexing throughput with GPU-accelerated vector indexing and NVIDIA cuVS.

Chris Hegarty

Exploring GPU-accelerated vector search in Elasticsearch with NVIDIA: Chapter I

Powered by NVIDIA cuVS, the collaboration looks to provide developers with GPU-acceleration for vector search in Elasticsearch.

Chris Hegarty

Lucene Wrapped 2024

2024 has been another major year for Apache Lucene. In this blog, we’ll explore the key highlights.

Chris Hegarty

Smokin' fast BBQ with hardware accelerated SIMD instructions

How we optimized vector comparisons in BBQ with hardware accelerated SIMD (Single Instruction Multiple Data) instructions.

Chris Hegarty

Making Lucene faster with vectorization and FFI/madvise

Discover how modern Java features, including vectorization and FFI/madvise, are speeding up Lucene's performance.

Chris Hegarty

Optimizing vector distance computations with the Foreign Function & Memory (FFM) API

Learn how to optimize vector distance computations using the Foreign Function & Memory (FFM) API to achieve faster performance.

Chris Hegarty

Understanding fused multiply-add (FMA) within vector similarity computations in Lucene

Learn how to use fused multiply-add (FMA) within vector similarity computations in Lucene and discover how FMA can improve performance.

Chris Hegarty

Ready to build state of the art search experiences?

Sufficiently advanced search isn’t achieved with the efforts of one. Elasticsearch is powered by data scientists, ML ops, engineers, and many more who are just as passionate about search as you are. Let’s connect and work together to build the magical search experience that will get you the results you want.

Try it yourself