How to Optimize Dedicated Servers for High Performance Elasticsearch Clusters?

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How to Optimize Dedicated Servers for High Performance Elasticsearch Clusters?Elasticsearch powers search engines, log analytics platforms, and real-time data applications across the world. However, many performance issues don’t come from Elasticsearch itself — they come from poorly optimized infrastructure.

In this guide by BeStarHost, we break down how to properly optimize a dedicated server for Elasticsearch, covering hardware selection, operating system tuning, and Elasticsearch performance best practices.

Why Dedicated Servers Are Ideal for Elasticsearch

Elasticsearch is extremely sensitive to CPU availability, memory pressure, and disk latency. Shared or oversold environments often cause:

  • Slow query response times
  • Unstable indexing performance
  • Frequent JVM garbage collection pauses
  • Cluster health issues

A dedicated server for Elasticsearch provides isolated resources, predictable performance, and full control over system tuning — all essential for production workloads.

Elasticsearch Hardware Requirements

CPU Selection

Elasticsearch benefits more from multiple CPU cores than from extremely high clock speeds.

  • Minimum: 8 CPU cores
  • Recommended: 16–32 cores for production
  • Use modern processors such as AMD EPYC or Intel Xeon

Memory (RAM) Best Practices

Memory plays a critical role in Elasticsearch performance.

  • Minimum: 32 GB RAM
  • Recommended: 64–128 GB RAM
  • Set JVM heap size to 50% of RAM (maximum 32 GB)

Keeping heap below 32 GB ensures compressed object pointers remain enabled.

Storage and Disk Performance

Disk I/O is often the main bottleneck in Elasticsearch.

  • Use NVMe SSD storage
  • Avoid HDDs entirely
  • Separate OS and data disks when possible

Operating System Optimization for Elasticsearch

Disable Swap

swapoff -a

Swapping causes severe performance degradation and should always be disabled.

Increase File Descriptor Limits

ulimit -n 65536

Kernel Parameter Configuration

vm.max_map_count=262144

This setting is mandatory for stable Elasticsearch operation.

Elasticsearch Performance Tuning Techniques

Shard Strategy

Too many small shards create unnecessary overhead.

  • Target shard size: 20–50 GB
  • Avoid over-sharding indices

Replica Configuration

Replicas improve availability but increase indexing load.

  • Use 1 replica for most production environments
  • Temporarily reduce replicas during bulk indexing

Refresh Interval Optimization

index.refresh_interval: 30s

Longer refresh intervals significantly improve indexing throughput.

Elasticsearch Cluster Optimization

  • Use dedicated master nodes for large clusters
  • Separate data, ingest, and coordinating nodes
  • Balance shards evenly across nodes
  • Continuously monitor cluster health

High-performance Elasticsearch starts with the right infrastructure. By selecting proper hardware, tuning the operating system, and applying Elasticsearch-specific optimizations, you can build a cluster that is fast, stable, and scalable.

At BeStarHost, our dedicated servers are purpose-built to handle demanding Elasticsearch workloads with ease.

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