.NET Parallel Programming

All about Async/Await, System.Threading.Tasks, System.Collections.Concurrent, System.Linq, and more…

PLINQ - .NET Parallel Programming

PLINQ and Int32.MaxValue

November 16, 2012 Nov 16, 2012 11/16/12
Stephen Toub - MSFT
In both .NET 4 and .NET 4.5, PLINQ supports enumerables with up to Int32.MaxValue elements.  Beyond that limit, PLINQ will throw an overflow exception.  LINQ to Objects itself has this limitation with certain query operators (such as the indexed Select operator which counts the elements processed), but PLINQ has it with more.This ...

PLINQ Queries That Run in Parallel in .NET 4.5

November 10, 2011 Nov 10, 2011 11/10/11
Igor Ostrovsky - MSFT
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 it believes will be faster. By default, PLINQ prefers to use a simple sequential algorithm ...

What’s New For Parallelism in .NET 4.5

September 17, 2011 Sep 17, 2011 09/17/11
Stephen Toub - MSFT
.NET 4 and Visual Studio 2010 saw the introduction of a wide range of new support for parallelism: the Task Parallel Library (TPL), Parallel LINQ (PLINQ), new synchronization and coordination primitives and collections (e.g. ConcurrentDictionary), an improved ThreadPool for handling parallel workloads, new debugger windows, new concurrency ...

PLINQ’s Ordering Model

June 21, 2010 Jun 21, 2010 06/21/10
Igor Ostrovsky - MSFT
In order to execute parallel queries as efficiently as possible, Parallel LINQ (PLINQ) treats ordering as optional. By default, PLINQ considers sequences to be unordered, unless the user explicitly opts into maintaining ordering using either the AsOrdered or the OrderBy operator.Roy Patrick Tan wrote a detailed article that...

Lesser-known Multi-threaded Debugging Support in Visual Studio 2010

May 25, 2010 May 25, 2010 05/25/10
Stephen Toub - MSFT
We’ve been very excited about the new debugging windows in Visual Studio 2010, namely Parallel Tasks and Parallel Stacks, as well as the newly revamped Threads window, and thus we’ve talked about them quite a bit. For an overview, you can read the MSDN Magazine article at https://msdn.microsoft.com/en-us/magazine/ee410778.aspx, and Daniel ...

ParallelExtensionsExtras Tour – #14 – SingleItemPartitioner

April 28, 2010 Apr 28, 2010 04/28/10
Stephen Toub - MSFT
(The full set of ParallelExtensionsExtras Tour posts is available here.) In a previous ParallelExtensionsExtras Tour blog post, we talked about implementing a custom partitioner for BlockingCollection<T>.  Custom partitioning is an advanced but important feature supported by both Parallel.ForEach and PLINQ, as it allows the ...

ParallelExtensionsExtras Tour – #11 – ParallelDynamicInvoke

April 15, 2010 Apr 15, 2010 04/15/10
Stephen Toub - MSFT
(The full set of ParallelExtensionsExtras Tour posts is available here.)  Delegates in .NET may have one or more methods in their invocation list.  When you invoke a delegate, such as through the Delegate.DynamicInvoke method, the net result is that all of the methods in the invocation list get invoked, one after the other.&...

F# PowerPack supports PLINQ

February 10, 2010 Feb 10, 2010 02/10/10
Stephen Toub - MSFT
The F# team has released the F# PowerPack for download on CodePlex, and we're very excited that the PowerPack now has direct support for PLINQ.  From the CodePlex site: F# Parallel LINQ IntegrationFSharp.PowerPack.Parallel.dll provides an F#-style API for parallel operations on sequences that are part of .NET 4.0 as System.Linq....