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The thread pool is managed by synchronisation context
Maximum number of threads governed by available virtual memory
Doing long-running work on a background thread is important to keep the UI thread available for user interaction
C# compiler generates a state machine (class implementing IAsyncStateMachine) from an await statement
Generated MoveNext() method is a big switch statement - a case for each time we use "await"
Non-awaited tasks hide exceptions
Never call Wait() on a Task
If you need to call an async method synchronously, use GetAwaiter().GetResult(). This gives us correct exception handling
Use ConfigureAwait(false) to avoid having to synchronise on the calling thread
Use ConfigureAwait(false) everywhere except the UI
If an async method doesn't do anything other than await another method, we can just return the Task directly to avoid a context switch
Don't do this from inside try/catch or using blocks
If the hot path in a method does not use the await keyword, return a ValueTask instead.
Don't call async Task methods from the constructor. Constructors should be fast.
async void should be avoided most of the time because exceptions won't be caught
Intellisense doesn't differentiate between void and async void
Non-UI applications won't have a SynchronizationContext, so don't need ConfigureAwait(false)
ConfigureAwait(false) needs to be called after every await, all the way down the method tree
Check out blog.stephencleary.com/2013/11/there-…
