Wait, What? C# Async-Await Explained
summary
Claims that C# async-await does not automatically run things in parallel but instead frees thread pool threads by emitting a continuation and relying on the OS completion mechanism IOCP. Demonstrates with HttpClient REST examples that awaiting sequentially is effectively synchronous, contrasts that with creating tasks and awaiting Task.WhenAll to get true overlap, uses a three-thread thought experiment and tens-of-thousands scale reasoning to show why this actually works for high-concurrency servers.
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chapters (13)
- 0:00Introduction
- 1:24Why async matters in C#
- 2:48Async vs sync analogy
- 4:54Code example surprises
- 6:17Problem async solves
- 8:05Thread pool mechanics
- 9:50Continuations free threads
- 12:00Async purpose and scalability
- 13:25Async in cloud essential
- 13:47Proper async with Task.WhenAll
- 15:14IO vs CPU work
- 17:01IOCP powers async
- 18:29Summary
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