I have finished three new videos that are about doing .NET GC Heap memory investigations using the PerfView tool and have posted them to Channel Nine.

1. Basics of .NET GC Snapshots
2. Investigating Memory Leaks: Part 1 Collecting the data
3. Investigating Memory Leaks: Part 2 Analyzing the data

The first video gives you the basics.  

• Determining whether you have a Memory problem and whether the problem is the GC heap.  
• Exactly happens when you take a heap snapshot (PerfView does sampling of large heaps). 

The second two videos describe a real life example:   How I used perfView's heap dumping capability to resolve a memory increasing issue in perfView itself.   I go through all the steps, from how the problem was first discoverd (by noticing memory growth in TaskManager) to finding a fix, and validating the the fix worked.  

You may also be interested in a background MSDN article that I helped write a few years back that is still very relevant  Memory Usage Auditing for .NET Applications.