Debugging Tools to Diagnose a Memory Leak

Debugging and diagnosing a memory leak or an OutOfMemoryException can be a daunting and challenging task. Fortunately, there are a number of tools to help; some of these are "paid license" apps, but there are even more tools that are free. There is a little bit of irony here; IMHO, the better tools are the free ones...

Free Tools

• Windows Task Manager: taskmgr.exe. Make sure to make the following columns visible:
• Memory - Working Set
• Memory - Private Working Set
• Memory - Commit Size
• Threads
• Handles
• USER Objects (if WinForm app)
• GDI Objects (if WinForm app)
• Windows Performance Monitor: perfmon.exe
• Process Explorer (SysInternals)
• VM Map (SysInternals)
• Debugging Tools for Windows (WinDbg, SOS, Kernel Debugger, etc.)
• Microsoft Debug Diagnostic Tool (DebugDiag)
• Psscor2 - WinDbg debugger extension for ASP.NET 2.0, 3.5
• Psscor4 - WinDbg debugger extension for ASP.NET 4.x
• SOSEX from Steve Johnson (.NET 2.0, 3.5)
• SOSEX 4 from Steve Johnson (.NET 4.x)
• IISInfo - WinDbg debugger extension (included with DebugDiag)
• Microsoft Application Verifier
• CLR Profiler 2.0 (good for finding heap fragmentation)
• CLR Profiler 4.0 (good for finding heap fragmentation)
• Windows Performance Toolkit (xperf)

Licensed Tools

• RedGate Ants Memory Profiler
• Micro Focus DevPartner Studio (formerly Compuware)
• SciTech .NET Memory Profiler
• AQ Time Pro

Hope this helps!

Want to have "WinDbg and SOS-like" features in VisualStudio?

While I've become adept at using WinDbg and all of it's extensions to do post-mortem crash-dump analysis, I've not yet ventured down the path of live-debugging strictly with WinDbg.  Maybe I'm dense, but it's anything but intuitive to me.  Call me "new-school" but there's just something about having a real UI while debugging that makes me more productive.

So, if you've ever needed to use some functionality of WinDbg or SOS (and any of the other extensions) while debugging in VisualStudio, there is some hope...

I've added 2 feature suggestions on the Microsoft Connect website for two features:

1. View an object's rooted references at runtime - https://connect.microsoft.com/VisualStudio/feedback/details/637376/add-feature-to-debugger-to-view-an-objects-rooted-references
2. View an object's memory footprint/usage - https://connect.microsoft.com/VisualStudio/feedback/details/637373/add-feature-to-debugger-to-view-an-objects-memory-footprint-usage

If either of these are something you'd like to see in an upcoming version of VisualStudio, please click the links above and vote for them!


As a side note, if you can't wait for the next version of VisualStudio, there are 2 different workarounds in the meantime:

1. Load SOS into the Immediate Window as documented here:  http://msdn.microsoft.com/en-us/library/yy6d2sxs.aspx
2. The other option is to stop at a breakpoint in VisualStudio, and then attach WinDbg in "non-invasive" mode.

While these workarounds seem to be mildly satisfactory, it'd be great if these features were already built in to the VS Debugger - so vote!