Is your application, server, or service delivering the appropriate speed of need? How do you know? Are you 100-percent certain that your latest feature hasn’t triggered a performance degradation or memory leak? There's only one way to verify - and that's by regularly checking the performance of your app.

But which tool should you use for this? In this blog post, we'll review the pros and cons of the leading open-source solutions for load and performance testing.

If you're like many, chances are you've already seen a great list of 53 of the most commonly used open source performance testing tools. However, the truth is many of these tools aren’t necessarily suited to our needs. Some are limited to the HTTP protocol. Some haven’t been updated for years. Most aren’t flexible enough to provide parametrization, correlation, assertions and distributed testing capabilities. Given the challenges most of us face today, I would whittle this down to a short list of the following five options that we will review in this post:
● The Grinder
● Gatling
● Tsung
● JMeter
● Locust

We’ll cover the main features of each tool, show a simple load-test scenario, and display sample reports. At the end, you'll find a comparison matrix to help you decide which tool is best for your project.

Just as a short note, if you are looking for a way to automate these open source tools, BlazeMeter created Taurus, our own open source test automation tool that extends and abstracts most of the above tools (as well as Selenium), and helps to overcome various challenges. Taurus provides a simple way to create, run and analyze performance tests. Make sure to check it out.

THE TEST SCENARIO AND INFRASTRUCTURE
For our comparisons we will use a simple a HTTP GET request from 20 threads with 100,000 iterations. Each tool will send requests as fast as it can. Let’s get started.

1. THE GRINDER
The Grinder is a free Java-based load-testing framework available under a BSD-style open-source license. It was developed by Paco Gomez and is maintained by Philip Aston. Over the years, the community has also contributed many improvements, fixes, and translations. The Grinder consists of:

● The Grinder Console - This GUI application controls various Grinder agents and monitors results in real time. The console can be used as a basic interactive development environment (IDE) for editing or developing test suites.
● Grinder Agents - Each of these are headless load generators can have a number of workers to create the load

Key Features of The Grinder:
1. TCP proxy to record network activity into the Grinder test script
2. Distributed testing that scales with an the increasing number of agent instances
3. Power of Python or Closure, combined with any …