Not long ago, software testers had every right to be nervous about performance testing. Frankly, most of the tools that were available deserved their fearsome reputations. Performance testing was more suitable for software developers than testers.

The introduction of IBM Rational Performance Tester changes the game. The same simplicity that the IBM Rational Software Development Platform brings to J2EE development is now available to those seeking a world-class, yet easy to use, performance testing solution.

Find Problems Faster
Simply put, if your development colleagues are already doing J2EE development using the IBM Rational SDP, there is no reason not to stress test what they build with IBM Rational Performance Tester. They're already benefiting from top-notch Eclipse-based tools. Why not add an arrow to your quiver by adopting IBM Rational Performance Tester?

Unlike most tools of this genre, IBM Rational Performance Tester is equally appealing to novice and expert users. Novices will find its point-and-click user interface refreshingly productive. Expert users, who also admire IBM Rational Performance Tester's inherent simplicity, will find a highly flexible tool that can test even the most complex applications.

IBM Rational Performance Tester was designed from the ground up to be a visual tool. There is no scripting language waiting to swallow you up. While many performance-testing tools now provide a "visual interface," they merely shield the tester from the scripting language that is hiding just below the surface. You either follow the path ordained, or get your hands dirtier than you bargained for.

In contrast, every important task in IBM Rational Performance Tester can be accomplished using the point-and-click interface. And, if for some reason you need specialized capabilities, test extensions can be created using industry-standard Java code.

Test Reality
IBM Rational Performance Tester deals especially well with the requirements of dynamic Web sites, where server responses may vary according to data a user entered. Often, these responses have a bearing on future information that will pass between client and server. IBM Rational Performance Tester can detect dynamic server responses and automatically make them accessible for re-use in tests involving subsequent server requests. This ensures that the test accurately simulates the system load of a real world user population.

Realistic performance testing also requires corresponding variations in test data. For example, when the test was recorded, a certain username/password combination may have been used. It is desirable to use a variety of username/password combinations during playback. The parameterization of such input values is supported through datapools. A datapool is a structured data source that is pre-populated with relevant data. Testers can easily assign datapool fields to page elements that expect user input.

Schedule Flexibility
In IBM Rational Performance Tester the creation of a test and the scheduling of the test are separate events. This allows testers to create a library of tests (i.e. browse inventory, add to cart, checkout, etc.) and schedule them to run in various proportions. For example, it would be simple to schedule the browse inventory test to run 80 percent of the time, add to cart for 15 percent, and checkout for the remaining 5 percent. More complex schedules, including those with loops and conditionals, can also be created visually.

The scheduling phase is where the number of virtual users and think times associated with the test run is specified. IBM Rational Performance Tester has a low memory and processor footprint so it easily scales to support very high user loads. It can also distribute the load across multiple load generation severs (including z/OS machines).

View Progress Now
There's no need to wait until the test run is complete to check the performance of your application. IBM Rational Performance Tester generates performance and throughput reports in real time, enabling you to detect performance problems at any time during a test run. These reports provide multiple filtering and configuration options that can be set before, during, and after a test run.

Testers can look at system-wide performance metrics such as processor utilization, disk activity, page faults, etc. or examine application-specific metrics such as page throughput and response times. Whatever metrics suit your needs, IBM Rational Performance Tester clearly presents information in a variety of useful charts and graphs.

Cross the Chasm
The capabilities of most performance testing tools stop at problem detection. You'll know which pages are slow but without knowing why they're slow (or how to fix the problem). Developers have little information to work with and must insert reams of debugging code into the application (which unfortunately changes its performance characteristics).

Since IBM Rational Performance Tester is based on the same platform as IBM Rational Application Developer, it naturally has the smarts to drill deeper into the problem. The companion IBM Performance Optimization Toolkit bridges the gap between problem detection and problem resolution by extending IBM Rational Performance Tester's analysis capabilities. The information it collects shows what happens beneath the hood of an application. It allows developers to find the root of problems by presenting detailed call chain timings in a variety of ways (such as UML2 sequence diagrams).

Speed Is on Your Side
While there are many tool choices in the world of performance testing, IBM Rational Performance Tester stands alone in its combination of ease of use and extensive features. It opens performance testing to testers of all skill levels and provides the insights into application behavior that can make the difference between success and failure.