Problem Diagnostics Lab Toolkit (PDTK) is a Web application that helps users to improve their problem diagnostic skills by reproducing various common problems, monitoring the impacts of different actions, and investigating the problems.

The tool will help you to understand common problems and to gain not only knowledge, but also experience, which plays a very important role in problem resolution. Problem Diagnostics Lab Toolkit can help developers gain a good understanding of the impact of typical bad code. The tool can enable system administrators to better understand symptoms of certain problems, thereby speeding the process of problem resolution.

How does it work?

Problem Diagnostics Lab Toolkit is a .ear file that is installed on WebSphere Application Server and accessed from a Web browser. The tool provides a Web Java code editor which help users to edit java code and invoke it immediately. Its integrated monitor will show detailed status of the application server. A built-in stress engine simulates workload on the embedded Java code. Users can use a dump facility to generate all kinds of dump files which will be used to diagnose certain problems.

Problem Diagnostics Lab Toolkit provides the following scenarios:

• Thread problems
• Wait leak
• Excessive synchronization
• Dead lock
• Memory problems
• Java memory leak
• Large object allocation
• Native memory leak
• Direct buffer leak
• High CPU usage
• Frequent GC
• Infinite loop
• JVM crash
• Stack overflow
• Jni error

Users can also add their own scenarios. Over time, it is expected to see more problem types and scenarios being consolidated into this tool.

Peng Fei Sui is a software engineer at IBM China Software Development Lab in Beijing, China. He joined IBM in 2006 and is currently working on WebSphere Application Server Servibility SVT. He is interested in WebSphere Application Server problem determination and often supports local customers.