Imagine a commuter rail system that is controlled by an individual standing at the end of the track logging each train as it arrives. Without a comprehensive tracking system that pinpoints each train while en route, it would be impossible for that person to identify and troubleshoot train delays. Instead, that person is left to "shoot from the hip," guessing at the possible cause of the delay. Web applications have the same limitation. Without a tool that offers a comprehensive look at the entire Web transaction, Web developers are left to guess and point fingers, instead of resolving performance issues. That's where Sitraka's PerformaSure 1.6 really shines.

PerformaSure is a performance analysis tool designed for multitiered, J2EE-based Web applications developed in the BEA WebLogic environment. Where traditional performance test tools only identify that the transaction took a long time, PerformaSure identifies which step in the multitiered process is responsible for the slowdown. This helps to eliminate costly misdiagnoses and speeds corrective action. PerformaSure is the ideal performance diagnostic tool for developers and implementers of complex systems with multiple application servers, databases, and Web servers.

PerformaSure is not for everyone. The complexity of installation and configuration and the intense resource requirements will be too cumbersome for smaller shops. Also, PerformaSure requires the use of software agents that are tightly integrated into each application and Web server along a transaction's path. This may make enterprise developers leery about installing this tool on production systems. Still, in development and preproduction environments, PerformaSure will provide invaluable information as developers shake out the performance bugs in their applications. And the more complex the application, the more valuable PerformaSure becomes.

Components
PerformaSure is comprised three main components: agents, the Nexus, and workstations. The PerformaSure Agents instrument the operating system and applications on each server. The agent is a vehicle whereby PerformaSure monitors various performance metrics of the system and of the specific applications and Java Virtual Machines in a distributed application. You will want to install agents at every step of the transaction's path, including the Web server, the application server, and the database server.

The PerformaSure Nexus is the central collection point for all of the monitored data. Based on our tests and on Sitraka's documentation, it is a resources-intensive application that is typically installed on its own system. Agents report their timing data to the Nexus, which correlates the events and stores the information in a database. During a load test of a distributed application, the Nexus will be deluged with information, so the processing and memory requirements are pretty high.

Making sense of all the data is the responsibility of the PerformaSure Workstation. The workstation is a GUI application that manages PerformaSure sessions, sets thresholds, and generates reports. It retrieves information from the Nexus and displays it graphically onscreen or in PDF reports.

How It Works
PerformaSure tracks a transaction through a distributed system, gleaning important performance metrics at every step of the way. In a simple Web application, a user visits a Web site and submits a request. That request is forwarded to a middleware application server, which in turn queries data from a database. From the user perspective, this all seems like a single, monolithic application. But behind the scenes, there are any number of systems working together to service the request. A delay in any of these will mean a delay in the user response time. Drilling down and identifying exactly which component is causing the delay is critical to identifying and correcting the bottleneck.

Traditional load and stress tests only identify overall application performance. However, by installing agents at each of these critical services, PerformaSure is able to not only report on overall system performance, but is also able to detect whether a performance problem is due to the network or to the application, to the database back end, or to slow server hardware. Pinpointing the exact source of the slowdown means less time is spent on troubleshooting.

We installed PerformaSure 1.62 on a Windows 2000 environment running BEA WebLogic 6.1. The version we had did not support the latest 7.0 version of WebLogic, which was disappointing. Supported application servers include BEA WebLogic Server 6.0 and 6.1. Web server support includes Apache 1.3.12 and other HTTP servers. (Note: PerformaSure v1.7 does support WebLogic Server 7.0.)

In addition to supporting these applications, PerformaSure includes operating system agents for AIX, Solaris, and Windows that track system resource utilization. This is essential for identifying whether or not a performance problem is due to the application or to insufficient or faulty hardware.

Overall, we were impressed with the amount and organization of the information provided by PerformaSure. The workstation software provided us with a wealth of information and troubleshooting control.

We had a love hate relationship with PerformaSure's installation. Installing the agents, Nexus, and workstation is incredibly easy, but configuring them to work correctly is not for the faint of heart. The problem is that getting the environment set up requires the QA engineer to manually modify the configuration files. Manually changing an Apache configuration file or monkeying with the JVM startup script is not our ideal of a smooth installation process. It would be nice if the Nexus, workstation and Agents had their own configuration utilities. Not to mention having to manually edit WebLogic configuration the files. In our case, where one test engineer set up the WebLogic environment and another installed and configured PerformaSure test tool, it became apparent that this is an enterprise test tool that requires an enterprise commitment.

When compared with competing products, such as CompuWare's ServerVantage, it is obvious that there is no simple way to simplify the configuration process. The good news is that once it is configured, everything should run smoothly. Then the bulk of your time will be spent analyzing results.

Summary
Overall, we give PerformaSure high marks in data acquisition and data organization - the two critical areas in performance optimization and troubleshooting. The flexibility in looking at your data and the simplicity of configuring projects will allow QA professionals to pinpoint bottlenecks quickly and easily. We did wish that configuring the PerformaSure software components were more streamlined.

Fortunately, once it's configured you won't have to deal with it. If you're concerned about Web application performance, PerformaSure will give you the information that you need instead of making you wait at the end of the line wondering why your train is late.

SIDEBAR
Company information
260 King Street East
Toronto, Ontario, Canada
M5A 4L5
1-800-663-4723
E-mail: info@sitraka.com

For sales, service, and presales information:
E-mail: direct@sitraka.com
Phone: 1-800-663-4723

Test environment:
Windows 2000 environment running BEA WebLogic 6.1