Designing and rewriting asynchronous tasks from scratch

on YouTube ↗01h 03m

" summary

Starts by building a minimal Task and TaskCompletionSource, then adds continuations, a TaskScheduler, and inlining so continuations can run concurrently; implements a state machine and custom TaskAwaiter/TaskBuilder to support async/await; demonstrates boxing and allocation pitfalls and fixes that reduce heap allocations; reproduces ConfigureAwait behavior and explains when ConfigureAwait(true/false) actually matters and why state machine boxing causes duplicate tasks; all code is implemented and runs.

AI-written summary · about

" chapters (9)

1. 0:00Introduction to async
2. 3:00Basic task implementation
3. 6:43Implementing continuations
4. 14:59Task scheduling and inlining
5. 22:41Reimplementing async/await
6. 30:13Abstracting awaitables
7. 36:15Performance optimizations
8. 50:11Context and ConfigureAwait
9. 56:50Q&A and conclusion

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