Legacy Documentation

This is the old XLT documentation which is here for reference purposes only. You can find the latest version at xltdoc.xceptance.com.

System Requirements


  • CPU at 1.5GHz or higher
  • 1.0 GB RAM
  • 1.0 GB available in the hard disk (default installation requires about 150 MB but test results might need additional capacity)


  • Operating System: Microsoft Windows, Linux, or Mac OS X, that is any operating system for which a JVM 8 (or higher) is available.
  • Browser: Firefox, Chrome, Internet Explorer 10, or Safari 6 for the HTML load reports. Note that JavaScript has to be enabled to utilize all functionality.

Installing XLT

Unzip the XLT archive to a file system location of your choice. The root directory is part of the archive, so you don’t need to create it separately. XLT supports spaces in the path; however, it’s easier to code tests when the path is free of them.

Make sure the executable directory of your Java installation is listed in your PATH environment variable so that the XLT start scripts can find the JVM runtime.

Script Developer is discontinued and not longer supported for all current Firefox releases.

To install the XLT Script Developer extension for Firefox, you need to:

  • Start Firefox.
  • Click File > Open File….
  • Navigate to the <XLT>/tools directory and select the .xpi file. The Add-on installation dialog appears.
  • Click Install to finish.

If the File Menu is not visible, you can also install the XLT Script Developer like this:

  • Start Firefox.
  • Open the Menu (The three horizontal bars on the upper right-hand side).
  • Click on Add-Ons.
  • Choose Extensions.
  • Click the gear symbol next to the Search bar.
  • Click on Install Add-On from File.
  • Navigate to the <XLT>/tools directory and select the .xpi file. The Add-on installation dialog appears.
  • Click Install to finish.

Alternatively, you can drag the .xpi file onto the Firefox window.

The XLT archive can either be obtained from the Xceptance website or from our Maven-compatible repository which allows users of Maven and Ivy to conveniently integrate XLT and all of its dependencies.

Updating XLT

Before you update XLT, it’s highly recommended to back up all modified files and project-specific or customized settings. In particular, this includes:

  • All your test suites (especially, when stored in a sub-folder of the XLT installation directory)
  • Result files (stored in <XLT>/results by default)
  • Generated load test reports (stored in <XLT>/reports by default)
  • Modified XLT properties files (<XLT>/config)

Download and install the latest XLT version from the Xceptance website as described above. You can have multiple XLT versions simultaneously since the name of the unpacked installation folder includes the version number by default.

Copy your backed-up files and directories to the corresponding place in the new XLT installation directory.

New test suite settings are provided in the default.properties file of the test suite testsuite-template. Copy it from <LatestXLTversion>/samples/testsuite-template/config to the config directory of your test suites <YourTestSuite>/config.

To update XLT Script Developer, go to File > Open File in the Firefox menu, and then open the latest .xpi file located at <LatestXLTversion>/tools. Alternatively, drag the .xpi file and drop it onto Firefox. If you work with Java-based test cases, add the updated XLT libraries to the Java build path of the Eclipse project. See Importing the Posters Test Suite into Eclipse for more information.

Note that when you configure your test project to use a newer version of XLT, do not forget to update XLT on your load machines as well. The version you have used to develop your test scripts must match the executing version of your load test environment.

Uninstalling XLT

Before uninstalling XLT, make sure to back up all test results and test reports you want to keep. To uninstall XLT, simply delete its installation directory. Use the Firefox Add-on dialog to remove the Script Developer Firefox extension.