Software Development Insights | Daffodil Software

13 Best Tools for Load Testing (Open Source) in 2024

Written by Nikita Sachdeva | Jan 31, 2024 9:30:00 AM

Load testing is a subset of performance testing that checks a system for its availability and response time during a concurrent load of users. It ensures that an application can handle the load without compromising performance. 

The metrics received from load testing (average response time, peak response time, error rate, concurrent users, requests per second) are utilized by the DevOps teams to design a load balancing approach. This further helps to optimize the resources on the server to manage the fluctuating demand during peak traffic times. 

From resource optimization to performance bottlenecks tracking, load balancing has several advantages in a software testing cycle. For example: 

  • Load testing minimizes the risk of downtime. It helps to keep a track of requests whose performance needs improvement and isolates them.

  • The report generated through load testing provides the right KPIs to the infrastructure team to utilize the resources efficiently.

  • Continuous load testing improves the deployment quality. It identifies the issues in application performance and fixes them on time for seamless deployments.

  • Load testing helps to optimize the cost of software and hardware resources. With an accurate capacity metric, the IT teams can manage costs associated with resources. 

For load testing of infrastructure, there are several open-source tools out there for the testers. In this blog post, we are going to share the top 7 load testing tools for API and automation testing. 

1. Apache JMeter



Apache JMeter is the most popular tool to load test functional behavior and measure the performance of an application. It can be used to test the performance of both static & dynamic resources. Different servers, applications, and protocols such as Web - HTTP, HTTPS (Java, NodeJS, PHP, ASP.NET), TCP, shell script, Mail - SMTP(S), POP3(S), and IMAP(S), etc. can be tested using Apache JMeter. 

2. Locust



Locust is a load testing tool that uses Python code to write the tests. It’s an event-based solution, i.e. a single process can handle thousands of concurrent users. The low overhead of Locust makes it suitable for testing highly concurrent workloads. Mozilla, Microsoft, Thought Works, and Intel AI are amongst the reputed clientele of the Locust load testing tool.



3. Gatling



Gatling is a tool for continuous load testing. It can be integrated with the CI/CD development pipeline. The platform has its own domain Specific Language (DSL) that makes test scenarios readable for everyone. With its continuous load testing ability, the tool proves to be a reliable solution for large-sized enterprise solutions. 


4. nGrinder



nGrinder is an open-source stress testing tool that helps to create, execute, and monitor tests. The test scenarios in nGrinder can be written using Jython or Groovy. Additionally, it has got web-based interface for report management, report monitoring, and project management as well. 

5. Siege



Seige is an HTTP load tester and benchmarking utility. It’s a command-line tool that lets the developers measure their code under stress. Siege allows to stress test a single URL with a definite number of simulated users. For multiple users, it reads the URLs into memory and then stresses them simultaneously. 

6. The Grinder



The Grinder is a Java load testing framework that helps to perform distributed testing using load injector machines. It helps to load test anything that has a Java API. The test scripts in the Grinder are written in Jython and Clojure languages. With the graphical console, multiple load injectors can be monitored and controlled. 

7. K6



K6 is a javascript-based load testing tool that allows testers to write testing scripts using JS language. It has JavaScript modules and libraries that can be used to build and maintain test suites. K6 can be integrated with the CI/CD pipeline. 

8. Vegeta


Vegeta is an open-source HTTP load testing tool and library that simulates a large number of HTTP requests in order to evaluate and analyze the performance of web services, servers, and applications. It was developed using the Go programming language and is frequently employed for benchmarking and performance testing.

Due to its ease of use, simplicity, and capacity for conducting effective performance tests, Vegeta is especially well-liked by developers and performance engineers. Although Vegeta is an effective tool for HTTP load testing, users should always make sure they have the necessary authorizations and are abiding by the law and ethical standards when testing web services and apps.



9. Tsung


Tsung is an open-source multi-protocol distributed load testing tool that supports HTTP and a handful of spin-offs (SOAP and WebDAV), MySQL and PostgreSQL databases, and XMPP. It was created in Erlang, a language specialized in high-performance applications, and can thus simulate extremely high traffic.

Tsung was developed by the French business Idealx at first, but a separate community is currently working on it. The GPLv2 license allows for the free software's publication.


10. Httperf



Httperf is a command-line utility designed for measuring web server performance. It generates workloads to evaluate transaction rates and server response times, providing detailed insights into a server's capabilities. It is well-suited for users seeking a tool for benchmarking and understanding server performance metrics. Httperf is distributed under the GPLv2 License, providing flexibility for different use cases.

11. Artillery



Written in NOde.js, Artillery is an expandable load testing toolset. It is released under the GNU Affero General Public License v3.0 and is well-known for its simplicity and ease of scenario definition through YAML configurations. It supports testing for both the HTTP and WebSocket protocols. If you need a robust yet easy-to-use solution for testing web apps and services, real-time systems, including chatbots and gameplay networks, Artillery is a good option.

12. FunkLoad


An open-source tool for functional and performance online testing, FunkLoad is built on the Python language. It was created to help developers and software testers automate web application testing to ensure that the apps meet the required speed and usefulness requirements.

FunkLoad is distributed under the GPLv2 License, offering openness for various testing needs.

13. Apache Bench



Apache Bench also referred to as ab, is a popular choice for stress testing and is an easy-to-set-up command-line tool. Due to its compact size and minimal resource requirements, Apache Bench is ideal for testing on servers or devices with lower processing power. 

It is included in the Apache HTTP server distribution and available under the Apache License 2.0. By producing a huge number of requests, it's a simple yet efficient tool for load testing and benchmarking HTTP servers.

Those looking for a quick and simple load testing solution who are acquainted with the Apache ecosystem should utilize it.

Want to Load Test Your Application? 

 

Load testing is an indispensable part of the software testing cycle. Depending upon the scale of the application, its complexity, and the number of users to be tested, a relevant load testing tool can be selected. 

At Daffodil, our software testing services include the use of the best tools to write test cases, perform tests, generate reports, and improve application performance. To understand how our QA team can help you out in testing your enterprise solution, connect with them