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How Many Systems Can a Single MetricsHub Agent Monitor?

To give our users a solid answer backed by real data, we recently conducted an in-depth load testing experiment using server emulation and real-world lab systems. Here's what we did, what we learned, and how you can interpret these findings for your own environments.

Introduction

“How many systems can I monitor with a single agent?” is one of the most common questions we get at MetricsHub. As simple as this question may sound, the answer is quite complex. It depends on several variables—such as the type of systems monitored, the communication protocol used, and the number of components per system. Monitoring a single server is one thing; monitoring a high-end storage system with thousands of volumes is something entirely different.

Test Methodology

Simulating Diverse Environments

We simulated a monitoring environment reflecting the diverse mix our customers typically deal with. Our emulations were based on the following protocols:

  • SNMP, which is traditionally known for being lightweight
  • HTTP REST API, which is increasingly common in modern IT infrastructures, although more demanding.

The simulated systems included the devices most monitored by MetricsHub:

  • HP ProLiant servers
  • Dell PowerEdge servers

Integrating Real Systems

To ensure realistic performance results, we also integrated a selection of real systems from our internal lab, including:

  • Regular Linux and Windows servers
  • NetApp and Pure Storage systems

MetricsHub load testing monitored systems

Monitoring Setup

To track the health of our testing infrastructure and agents, we used:

This setup allowed us to monitor:

  • The MetricsHub Agent itself MetricsHub load testing MetricsHub process

  • The Prometheus server MetricsHub load testing Prometheus process

  • the Grafana server MetricsHub load testing Grafana process

  • Key metrics such as CPU usage, memory consumption, and job queue status MetricsHub load testing Prometheus key metrics

Key Findings

Finding #1: Protocol Matters (A Lot)

  • SNMP allows scaling efficiently and remains a go-to for lightweight monitoring.
  • HTTP/REST introduces heavier loads

Finding #2: Agent Tuning is Critical

The MetricsHub Agent offers several parameters that can be tuned to enhance performance. One of the most impactful was jobPoolSize, which governs how many jobs the agent can handle concurrently.

Proper tuning ensured smooth performance even under heavy load.

Finding #3: Keeping an Eye on the Monitors Pays Off

Monitoring Studio X offered a real-time view of the health and behavior of the monitoring stack and was essential in:

  • Preventing resource bottlenecks
  • Understanding how changes impacted performance
  • Planning future scalability strategies

Practical Recommendations

Based on our tests, we recommend:

  1. Starting with SNMP whenever possible since it is lighter and sufficient for many server types.
  2. Monitoring your agent resources closely and tuning parameters like jobPoolSize if using REST.
  3. Using a secondary monitoring layer (in our example, Monitoring Studio X) to observe agent behavior and system health under load.
  4. Assessing your system complexity: A single high-end storage array might consume more resources than 50 standard servers.

Real-Time Monitoring Stats

At the end of our load test, a single MetricsHub Agent was successfully monitoring 734 systems, including:

  • 200 Dell PowerEdge 740 XD systems via SNMP v2c
  • 200 Dell PowerEdge R640 systems via HTTP REST
  • 200 HP ProLiant DL380 systems via SNMP v2c
  • 100 HP Synergy 480 systems via HTTP REST
  • additional lab systems (Pure, NetApp, and others.)

MetricsHub load testing monitored systems

We proudly achieved 100% monitoring coverage, meaning every system was actively reporting data and fully represented in MetricsHub dashboards.

MetricsHub load testing full coverage

This was made possible by leveraging a mix of protocols and notably:

  • SNMP: 48%
  • HTTP (REST): 48%
  • SSH/WMI/Other protocols: 4%

Conclusion

While there’s no one-size-fits-all answer, our testing shows that with proper configuration, a single MetricsHub Agent can reliably monitor hundreds of systems, even with a mix of protocols. Currently, we have reached 734 monitored systems with full coverage—and the system is holding strong.

Have questions about how this applies to your infrastructure? We’d love to help. Contact our support team or start a conversation in the MetricsHub community.

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