Choosing an Automated Testing Tool (Continued)

Load-Testing Tools
This category, also called performance or stress testing tools, tests what happens to the code as the application scales with multiple users in a simulated environment. The tools test, among other things, whether performance degrades as the load is increased. Once bottlenecks are found, these tools can determine the source of the problem and begin fixing it. Key tools in this area include:

• LoadRunner (Mercury Interactive). LoadRunner offers a host of capabilities, including WAN emulation support, and support for Java, Citrix MetaFrame, XML and other environments. A Web transaction breakdown monitor helps isolate performance problems, while the tool's data wizard helps developers create data-driven tests quickly. In addition, the new tuning module add-on provides component test libraries and a knowledge base that helps isolate and resolve performance bottlenecks, according to the company. Mercury Interactive's Astra LoadTest is a similar tool for the Web environment.
• SilkPerformer (Segue). Developers can simulate virtual users working with different Web, middleware and database protocols. Root cause analysis tools and management reports help this load testing tool isolate problems, and verification under load helps ensure that functional errors are detected under load conditions.
• Test Perspective, Load Test Edition (Keynote Systems Inc.) enables developers to test the capacity of their Web-based applications before going live. Developers can download a script recorder from Keynote's testing portal to record their own scripts. Once recorded, developers can then run tests immediately or schedule them for later.
• QACenter, Performance Edition (Compuware). This automated testing tool combines load testing, server monitoring and data management tools to establish testing environments, load test applications and monitor the effect of load on underlying servers, applications and databases while pinpointing problems.
• e-Load (Empirix). Part of the e-TEST suite, e-Load tests the performance of Web-based applications through reusable visual scripts, a scenario manager that allows developers to define custom load scripts, and application server support for a wide variety of development environments. In addition, it allows users to create data-driven load tests without programming and vary the number and type of users during a performance test.
• Rational Suite TestStudio (IBM Rational). Users employ Rational Robot to capture and create both Virtual User and GUI tests, and use TestManager to schedule, execute and analyze the results of the tests. TestStudio allows testers to quickly build complex usage scenarios without programming to emulate user-type activities in sequential, random or synchronized patterns. By weighting the various user groups in the schedule, the tool produces realistic system loads. Once created, the load test can be scaled up to tens of thousands of users without having to create a new schedule for each user count.