#it3xl

Async execution - It's all about responsiveness. Old code scenarios To use WaitHandle from a Task. Implement the APM pattern by FromAsync methods and "Tasks Forest" Implement the EPM pattern by TaskCompletionSource. Asynchronous Task means the Threadless Task. Asynchronous Tasks may have only the next statuses: Fault, RunToCompletion, Cancelled. Continuation for Asynchronous Tasks Use the TaskCompletionSource<T> class. async await A syntactic sugar for awful amount of work. A compiler's underground job. A enumeration, try, finally, using and etc. Users SynchronizationContext implicitly. Unwrap multiple exceptions The await will return only the first exception from a AggregateException. There is a useful trick to unwrap multiple exceptions. await task.ContinueWith(     ( ) => { } ,     TaskContinuationOptions. ExecuteSynchronously ); var results = task .Result; Multiple await Preventing of lost exceptions wit...

Asynchronous Programming Parallel Programming Multithreaded Programming

Parallel execution - It's all about loaded computations. Common Types of Parallelism Data     amount of data processed by one operation in parallel. Patterns     Parallel Loops Implementations     Parallel.Foreach     Parallel.For Task     Some data or amount of data processed by many operations. Patterns     Parallel tasks Implementations     Parallel.Invoke Dataflow     Operations processed in some flow or order. Patterns     Features     Pipeline Embarrassingly parallel     computations entirely independent of one another. No dataflow in between the options. Patterns Parallel Loops Parallel.For / Parallel.Foreach Parallel Tasks Parallel.Invoke Parallel Aggregation Map- Reduce Producer-Consumer By Parallel Loops with TLS (Task Local Storage) parameter or by Wait All One By One Futures Dynamic Task Parallelism Pipelines + Concurrent D...

Synchronization primitives Semaphore Slim

IAsyncResult needs to be closed.

How to invoke an event or delegate handlers asynchronously Variant with the  Parallel class (TPL). public void OnMyEvent( String myValue) {     var multiCastDelegate = Interlocked .CompareExchange( ref MyEvent, null , null );     if (multiCastDelegate == null )      {         return ;      }     var handlers = multiCastDelegate.GetInvocationList()         .Cast< EventHandler < MyEventArgs >>();     var args = new MyEventArgs (myValue);     Parallel .ForEach(         handlers,         handler => handler( this , args)); }   Old variant with the Asynchronous delegates (APM). public void OnMyEventOld( String myValue) {     var multiCastDelegate = Interlocked .CompareExc...

Plain Threading     Thread.Sleep(0) vs Thread.Yield()     Foreground and Background Threads     finally blocks in the execution stack of background threads are circumvented         (including using)     Thread Priority     Memory-mapped files     Exception Handling         Swallow of an exception in the main thread.         Centralized exception handling             global event             only for an UI thread             AppDomain.CurrentDomain.UnhandledException                 app will shutdown or <legacyunhandledexceptionpolicy> Thread Pooling     Thread.CurrentThread.IsThreadPoolThread     Oversubscription         hill-climbing algorithm   ...