The Debug Diagnostic Tool (DebugDiag) is designed to assist in troubleshooting issues such as hangs, slow performance, memory leaks or fragmentation, and crashes in any Win32 user-mode process. The tool includes additional debugging scripts focused on Internet Information Services (IIS) applications, web data access components, COM+ and related Microsoft technologies.
DebugDiag was released as part of the IIS Diagnostic toolkit and as a standalone tool. DebugDiag 1.1 is currently available as a standalone tool.
DebugDiag provides an extensible object model in the form of COM objects and provides a script host with a built-in reporting framework.
It is composed of the following 3 components; a debugging service, a debugger host, and the user interface.

The Debugging Service
The debugger service (DbgSvc.exe) performs the following tasks:

• Attach/Detach the host to processes
  
• Collect performance monitor data
  
• Implement HTTP ping to detect hangs
  
• Inject leak monitor in running processes
  
• Collect debugging session state information
  
• Shows the state of each rule defined

The Debugger Host
The Debugger Host (DbgHost.exe) hosts the Windows Symbolic Debugger Engine (dbgeng.dll) to attach to processes and generate memory dumps. It also hosts the main analyzer module to analyze memory dumps. Dbghost.exe has no dependency on the service “DbgSvc.exe” and can be used separately.

The User Interface
The user interfaces (DebugDiag.exe and DebugDiagAnalysisOnly.exe) present an interface to analyze memory dumps, automate the creation of control scripts and show the status of running processes, including services.

It is composed of 3 views:

• Rules: Creates control script for the debugger host through a wizard. The script is located under scripts
  
• Advanced Analysis: Runs a selected “Analysis Script” against one or more memory dumps.
  
• Processes: Shows status of running processes/services