For .NET 4.5, we’ve invested quite a bit of effort into performance, and in particular for the Task Parallel Library (Joe Hoag wrote a good paper covering some of these improvements).  We focused such effort on TPL because it is a core component...

In Part 1 and Part 2 of this short series, I demonstrated how you can build a SynchronizationContext and use it run an async method such that all of the continuations in that method will run on serialized on the current thread. This can be helpful when...

I’ve previously blogged about how to expose existing Asynchronous Programming Model (APM) implementations as Task-based methods.  This can be done manually using a TaskCompletionSource<TResult>, or it can be done using the built-in wrapper...

Yesterday, I blogged about how you can implement a custom SynchronizationContext in order to pump the continuations used by async methods so that they may be processed on a single, dedicated thread.  I also highlighted that this is basically what...

I recently saw two unrelated questions, the answers to which combine to form a potentially useful code snippet. The first question was about SynchronizationContext. SynchronizationContext provides a Post method, which asynchronously schedules the supplied...

When I discuss the new async language features of C# and Visual Basic, one of the attributes I ascribe to the await keyword is that it “tries to bring you back to where you were.” For example, if you use await on the UI thread of your WPF...

Recently I’ve heard a number of folks asking about Task.Start, when and when not to use it, how it behaves,and so forth.  I thought I’d answer some of those questions here in an attempt to clarify and put to rest any misconceptions about what it...

The System.Net.Sockets.Socket class in .NET exposes multiple sets of asynchronous methods that perform the same basic operations but that are exposed with different patterns. The first set follows the APM pattern, where for a synchronous method like...

TPL Dataflow includes a number of built-in, already-implemented blocks that target the most common scenarios. Additionally, some flexibility is provided by the set of options that may be used to tweak block behaviors. However, a developer may still choose...

In the .NET Framework 4.5 Developer Preview, you’ll find that CancellationTokenSource now has timeout support built directly into its implementation. This makes it very easy to create a token that will automatically have cancellation requested after...

In a previous article, How to use C++ AMP to C# , we described how you can use P/Invoke to call into C++ AMP and accelerate your C# apps on GPUs and other heterogeneous hardware. In this post, we'll take a look at how the same task becomes easier in Windows...

Available since .NET 4, ThreadLocal<T> is a container that holds a separate value for every thread. In practice, ThreadLocal<T> is often convenient for storing per-thread counters, resources, or partial results. As mentioned earlier on this...

One interesting thing to know about PLINQ is that not all queries are guaranteed to execute in parallel (See PLINQ Queries That Run Sequentially for reference). You can think of the AsParallel method as a hint to run in parallel for query shapes that...

We invested a lot of time into making parallel programming “just faster” for .NET 4.5.  You’ve already seen some neat tricks to ConcurrentDictionary .  There’s a lot more to say about improving the performance of the Task Parallel Library, and...

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...

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...

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...

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...

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...

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...

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...

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...

“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...

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...

It’s been a few months since April when we last released a Community Technology Preview (CTP) of System.Threading.Tasks.Dataflow.dll, aka “TPL Dataflow”. Today for your programming pleasure, we have another update. As mentioned in...