Codexworker

Elasticsearch Optimization

Slow searches, high CPU on data nodes, cluster instability, or a mapping that's impossible to change — Elasticsearch problems usually come back to queries, mappings and shard strategy.

I review your queries, mappings, index settings and shard layout, and fix what's actually expensive for your data and query patterns.

I'm a backend developer with 10+ years of experience across PHP, Go, MySQL and Elasticsearch. Recent work includes Cenoskop (30M+ products daily), Niftycent (US price intelligence), and facha.sk (Go backend). I build, fix and optimize backend systems that handle real data and real traffic.

What I Can Help With

Optimize Elasticsearch queries, mappings, indices and cluster configuration.

Typical Problems

slow search queries high CPU on data nodes expensive aggregations mapping explosions shard imbalance hot threads fielddata pressure indexing throughput problems cluster stability issues

Relevant Experience

Tuned Elasticsearch for Cenoskop's product search — reduced aggregation query time from 8s to 400ms by redesigning the mapping (switching from analyzed text to keyword for faceted search), adjusting shard size, and rewriting aggregation queries to use filters instead of query context.

What Is Included

mapping review
query analysis (profile API)
index settings review
shard strategy review
aggregation optimization
heap and fielddata analysis
prioritized recommendations

How It Works

You export cluster state, mappings, representative slow queries (with profile API output) and node stats. I analyze the query patterns, mapping choices, shard layout and resource usage, then propose specific fixes. Most engagements take one to two days.

Starting from €599

Profiling and a written set of prioritized recommendations. Implementation of changes is quoted separately.

Frequently Asked Questions

Is my mapping fixable without reindexing?

Most mapping changes (analyzers, field types, disabled norms) require a reindex into a new index. I'll flag which fixes are live and which need a reindex window.

What data do you need?

GET _cluster/stats, GET _nodes/hot_threads, the slow search log, and the profile API output for a few representative slow queries, plus the relevant mapping.

Related Services

Other problems I help with.

Elasticsearch Performance Tuning

Tune Elasticsearch for your specific query and data patterns.

Details →

Custom Elasticsearch Development

Implement Elasticsearch for search, analytics and indexing.

Details →

Elasticsearch Migration & Upgrade

Migrate to or upgrade Elasticsearch with minimal downtime.

Details →

Backend Performance Audit

Find and prioritize the real bottlenecks across your full backend stack.

Details →

Systems I've Built

Relevant production work.

Price Intelligence Engine

Cenoskop / Levnobot

Crawler monitoring millions of products. Processing 30M products daily and comparing them.

Built and maintain the full crawling pipeline — from scraping through Elasticsearch indexing to price comparison.

Data Aggregation Scraping ElasticSearch
US Price Intelligence

Niftycent

Price intelligence engine for the US market. Processing large-scale product data.

Built the data pipeline and crawling infrastructure for large-scale US product monitoring.

Data Aggregation Scraping Big Data

Need Help With This?

Describe the problem in a few lines — I'll look at it and tell you what I think.

Request an Elasticsearch optimization