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ClusterLoader2

Free plan Self-hosted

What ClusterLoader2 is

ClusterLoader2 is a self-hosted tool for load testing Kubernetes clusters and the official framework for Kubernetes scalability and performance testing. Tests describe a target cluster state, how quickly to reach it, and which performance characteristics to measure. Configurations can be written in YAML or JSON, with templating and parameter overrides for Kubernetes objects. Measurements include API availability and responsiveness, CPU and memory profiles, etcd and scheduler metrics, pod startup latency, and resource usage summaries. Prometheus provides extra cluster observability and can scrape pod metrics through ServiceMonitor or PodMonitor; API responsiveness measurements are skipped if a Prometheus server is unavailable. Its Module API supports parameterized configuration modules that tests or other modules can reuse. Running a test requires paths to a kubeconfig file and test configuration, plus a cluster provider. Options include gce, gke, kind, kubemark, aws, local, vsphere, and skeleton. The getting-started guide covers repository setup, creating a Kind cluster, writing and running a test. Its tutorial requires Go, and the general-purpose load test is described for clusters from 100 to 5,000 nodes. ClusterLoader2 is free and open source under Apache-2.0.

Who it suits

ClusterLoader2 suits people working with Kubernetes who need to run configurable load and performance tests on a cluster. Its listed provider options include Google Cloud, AWS, VMware vSphere, and local or Kind environments.

What it does well

Measures API, scheduler, etcd, and pod performance
Supports reusable, parameterized configuration modules
Prometheus can scrape pod metrics
Free and open source under Apache-2.0

What to know first

Requires kubeconfig and test configuration paths
API responsiveness measurements need a Prometheus server
Getting-started tutorial requires Go

Verdict

ClusterLoader2 offers configurable Kubernetes load tests with a broad set of measurements and provider options. Account for its cluster, configuration, and Prometheus requirements when planning a test.

Facts from ClusterLoader2's own pages

Cluster access: Running a test requires paths to a kubeconfig file and test configuration, plus a cluster provider. · github.com, 4 Oct 2026
Cluster providers: The command-line provider options listed are gce, gke, kind, kubemark, aws, local, vsphere, and skeleton. · github.com, 9 Oct 2026
Configuration modules: The Module API lets users split test configurations into reusable, parameterized module files. · github.com, 9 Oct 2026
Getting started: The getting-started guide walks through setting up the repository, creating a Kind cluster, writing a simple test, and running it. · github.com, 4 Oct 2026
Intended users: The repository says it stores Kubernetes-related performance testing tools and invites users to contact the owners to add a load test, benchmark, framework, or other tool. · github.com, 4 Oct 2026
License: The perf-tests repository includes the Apache License, Version 2.0, which grants no-charge, royalty-free copyright and patent licenses subject to its terms. · github.com, 9 Oct 2026
Measurements: Available measurements include API availability and responsiveness, CPU and memory profiles, etcd metrics, pod startup latency, resource usage, and scheduling throughput. · github.com, 9 Oct 2026
Observability: ClusterLoader2 provides extra cluster observability during tests with Prometheus. · github.com, 4 Oct 2026
Prerequisite: The getting-started tutorial requires Go and demonstrates creating a cluster with Kind before running a test. · github.com, 9 Oct 2026
Pricing and trial: The opened project pages provide no commercial plan pricing or trial terms. · github.com, 9 Oct 2026
Prometheus: ClusterLoader2 provides cluster observability with Prometheus and supports scraping pod metrics through ServiceMonitor or PodMonitor. · github.com, 9 Oct 2026
Prometheus integration: ClusterLoader2 can scrape pod metrics using ServiceMonitor or PodMonitor. · github.com, 4 Oct 2026
Prometheus requirement: API responsiveness measurements are skipped when a Prometheus server is unavailable. · github.com, 4 Oct 2026
Provider options: The required provider flag accepts gce, gke, kind, kubemark, aws, local, vsphere, or skeleton. · github.com, 4 Oct 2026
Purpose: ClusterLoader2 is a Kubernetes load testing tool and the official Kubernetes scalability and performance testing framework. · github.com, 9 Oct 2026
Reusable modules: The Module API lets users split test configurations into parameterized modules that can be reused by tests or other modules. · github.com, 4 Oct 2026
Scale: The getting-started guide says its general-purpose load test can be used for clusters from 100 to 5,000 nodes. · github.com, 9 Oct 2026
Templating: Test definitions and Kubernetes object definitions support templating, with parameters and overrides available. · github.com, 9 Oct 2026
Test cleanup: The guide says ClusterLoader2 deletes namespaces it creates automatically by default. · github.com, 9 Oct 2026
Test configuration: Test definitions can be written in JSON or YAML and support templating. · github.com, 4 Oct 2026
Test format: Tests use YAML and describe desired cluster states and how quickly those states should be reached. · github.com, 9 Oct 2026

Where ClusterLoader2 stands on Freedom251

Infrastructure Testing Tools#19 of 28