Debugging asynchronous scenarios in .NET

on YouTube ↗01h 00m

" summary

Reconstructs async causality by walking runtime objects and continuations to find the actual blocking point: uses WinDbg and Visual Studio to open dumps, inspects ActionBlock internals and finds a completion task faulted with a SocketException that prevents shutdown, and uses SOSX/ref and a custom grunt extension to follow continuations back to the awaiting state machines. Shows thread‑pool starvation where synchronous Task.Wait on Task.Run/LongRunning plus global/local queue behavior inflates threads (observed ~1,466 threads) and the fix is to stop blocking on tasks.

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" chapters (12)

1. 0:00Start
2. 3:32Debug Windows and Parallel Stack
3. 4:51Check the Source Code
4. 5:52The Action Block
5. 14:10Retrieve the Address of the Action Block
6. 14:35Get the Address of an Object
7. 26:41The Source Code of the Node Object
8. 30:10Print Exception
9. 33:03Timer Information
10. 40:48The Windows Calculator
11. 43:45What Is a Task Scheduler
12. 58:31Conclusion

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