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Astra LoadTest 3.0: Grooming users for real scalability testing

• By Celeste Sargent
• January 1, 2001

Software Quality Partners’ Nashua, N.H., Lab recently evaluated Astra LoadTest Version 3.0, an automated testing tool for transactional Web apps. The tool helps users simplify Web load testing, and answers the questions “How well does the Web app perform?” and “Will it scale as more users access the site?”

As users navigate through their application in the browser, Astra LoadTest automatically captures each action performed. Actions are displayed in a collapsible Test Tree.

Installing just Astra LoadTest from the Astra demo CD was easy. A “typical install” installs the Virtual User Recorder and Controller and requires 62.7Mb. The “compact install” requires the same 62.7Mb and installs the same two components. A “custom install” lets a user install the same two components or just the Controller on a load-generation machine and requires 94.2Mb. While the terminology is rather confusing, the installation procedures apparently work as intended. In addition, users must also download and install Microsoft’s Script Debugger from Microsoft’s Windows Script Technologies site to use the product’s debugging feature.

Astra LoadTest additionally requires that in Internet Explorer users set the “Browse in a new process” and “Disable script debugging” in the “Advanced” tab of “Internet Options” during the install process. If LoadRunner’s TestDirector is already installed on your machine, the BDE directory will also have to be renamed.

Users can generate an automated test with Astra LoadTest by recording the processes performed on the Web application with the Virtual User Recorder. As users navigate through their application in the browser, Astra LoadTest automatically captures each action performed. The actions are displayed in the form of a collapsible icon-based tree called the Test Tree. Users can insert Start and End transactions into the test to enable the Controller to measure the performance of their Web server under various load conditions. The recorded test becomes part of the scenario that will test the Web application.

A test can be enhanced through the use of parameterization, runtime settings and verification. For example, when testing an application that contains a login page, a single set of test code that uses “parameterization” lets you use a different login name and password each time. In contrast, test code with the login name and password “hard-coded” has to be duplicated and edited to pass a different name and password to the login screen. Runtime settings are used to configure how Virtual Users behave when the test is run. Verification is accomplished by inserting a checkpoint to confirm that the application is functioning correctly; this is done by comparing an application component to an expected value.