Showing category results for .NET Parallel Programming

Imagine that you have a Task handed to you by a third party, and that you would like to force this Task to complete within a specified time period. However, you cannot alter the “natural” completion path and completion state of the Task, as that may cause problems with other consumers of the Task. So you need a way to obtain a copy or “proxy” of th...

A “dataflow block” is represented by a class implementing the IDataflowBlock interface. The state of a dataflow block is represented by the state of its IDataflowBlock.Completion Task, which itself has a Status property. When a dataflow block is in active state, meaning that it is currently doing processing or may do more processing in the future, ...

ConcurrentDictionary is a popular concurrent data structure that was introduced in .NET 4. In the .NET 4.5 release, ConcurrentDictionary gets two performance improvements. One optimization is related to the way ConcurrentDictionary avoids torn reads and writes. To explain the background, all reference types and some value types are guaranteed to b...

In April, we released the Async CTP Refresh, and since then we've seen fantastic adoption of the technology.  We've also seen the technology landscape evolve.  Windows Phone 7.5, aka "Mango", was released.  Silverlight 5 has had both a Beta and an RC release.  And there have been multiple patches to Visual Studio and the .NET Fr...

When you start using async methods heavily, you’ll likely see a particular pattern of composition pop up from time to time.  Its structure is typically either of the form: async Task FooAsync() {     … // some initialization code without awaits      await BarAsync(…); ...

In .NET 4, Task.Factory.StartNew was the primary method for scheduling a new task.  Many overloads provided for a highly configurable mechanism, enabling setting options, passing in arbitrary state, enabling cancellation, and even controlling scheduling behaviors.  The flip side of all of this power is complexity.  You need to know w...

The October 2011 issue of MSDN Magazine is now available online.  In it, you can find three articles about the new async/await features of C# and Visual Basic.  While the articles can stand alone, they were written with each other in mind in order to provide a 1-2-3 on-ramp into the world of asynchronous programming with these new languag...

Consider a type that will print out a message when it’s finalized, and that has a Dispose method which will suppress finalization: class DisplayOnFinalize : IDisposable {     public void Dispose() { GC.SuppressFinalize(this); }     ~DisplayOnFinalize() { Console.WriteLine(“Finalized”); } } Now conside...

“Don’t forget to complete your tasks.”  That guidance may sound trivial and silly, but I recently saw it as a source of a bug in software written by some very smart folks, and thus thought this would be a good opportunity to remind folks of the imperative.Tasks represent a promise.  If you hand one out, someone else may&...

For the .NET Framework 4.5 Developer Preview, a lot of work has been done to improve the Task Parallel Library (TPL), in terms of functionality, in terms of performance, and in terms of integration with the rest of the .NET Framework.  With all of this work, we’ve strived for a very high compatibility bar, which means your applications t...