An overview of… Luis Guerrero Plain Concepts

 Finding exploitable parallelism  Organizing by Tasks  Organizing by Data  Organizing by Ordering

 Linear or recursive?  Task parallel  Divide and conquer  Enough task?  Too many – thrashing  Too few – under utilization  Dependencies between tasks  Scheduling work to tasks {}

 Work per task?  Small workloads  Variable workloads  Dependencies between tasks?  Removable  Separable  Read only or read/write {}

 Linear or recursive?  Geometric decomposition  Recursive data  Data “chunk” size?  Too big – under utilization  Too small – trashing  Chunk layout?  Cache and cache line size  False cache sharing {}

 Implementation Patterns  Fork / Join  Loop Parallel  Divide and Conquer  Producer / Consumer  Pipeline  Asynchronous Agents

 Task Parallel Library  Parallel LINQ (PLINQ)  Data Structures for Parallel Programming  Parallel Diagnostic Tools

 Data parallelism: The Parallel Class  Parallel  For  For<>  Foreach  Invoke

Parallel class

 Task is the minimum unit of work in TPL  Can be scheduled by request  2 Scheduled inside.NET box, ThreadPool y UI  Can have a result  Is observable  Can be continue with another task  Can be securely cancelled  Someone can wait for a completion

Creating Tasks

Task continuation

Exceptions and cancellation support

A Barrier is a synchronization primitive that enforces the stopping of execution between a number of threads or processes at a given point and prevents further execution until all threads or processors have reached the given point. A CountdownEvent is a synchronization primitive that enables ongoing tracking of a given workload in order to determine if processing of that workload is finished or not.

Barrier y CountdownEvent

PLINQ

An introduction to….

The Managed Extensibility Framework (MEF) is a new library in.NET 4 for building applications that can be incrementally extended.  For customers  For you and your team  Always there, always ready

The Managed Extensibility Framework (MEF) is a new library in the.NET Framework that enables greater reuse of applications and components. Using MEF,.NET applications can make the shift from being statically compiled to dynamically composed

In software engineering, extensibility is a systemic measure of the ability to extend a system and the level of effort required to implement the extension.

Software entities should be open for extension, but closed for modification.

KnownUnknown VS.

 An Application is built of parts.

 Export it.  Import it.  Compose it.

Widget1 [Export(typeof(UserControl))] public class Widget1 : UserControl { public string Message { get{return(string) Button.Content;} set{Button.Content=value;} } Export

Widget1 [Export(typeof(UserControl))] public class Widget1 : UserControl { [Import] public string Message { get{return(string) Button.Content;} set{Button.Content=value;} } Import

Widget1 [Export(typeof(UserControl))] public class Widget1 : UserControl { [Import(“HelloMEF.Message”)] public string Message { get{return(string) Button.Content;} set{Button.Content=value;} } Import

Main Page [Export(typeof(UserControl))] public class MainPage: UserControl { [ImportMany(typeof(UserControl))] public IEnumerable { get;set; } ImportMany

PartIntializer: “Compose yourself” Main Page Compose public MainPage() { InitializeComponent(); PartInitializer.SatisfyImports(this); }

Widget1 [ExportMetadata(“Location”,Location.Top)] [Export(typeof(UserControl))] public class Widget1 : UserControl { public string Message { get{return(string) Button.Content;} set{Button.Content=value;} } Export

Main Page [Export(typeof(UserControl))] public class MainPage: UserControl { [ImportMany(typeof(UserControl))] public IEnumerable { get;set; } ImportMany

Widget1 [ExportMetadata(“Location”,Location.Top)] [Export(typeof(UserControl))] public class Widget1 : UserControl { public string Message { get{return(string) Button.Content;} set{Button.Content=value;} } Export

Widget1 [Widget(Location=Location.Top)] public class Widget1 : UserControl { public string Message { get{return(string) Button.Content;} set{Button.Content=value;} } Export

Container

Catalog

Container Catalog TypeCatalog AssemblyCatalog DirectoryCatalog AggregatingCatalog

Part B Export Export [Import(typeof(ILogger))] public ILogger Export Logger { get; set; }

Container Part A Part B [CompositionOptions(CreationPolicy=CreationPolicy.NonShared)] [CompositionOptions(CreationPolicy=CreationPolicy.Shared)] Shared Non-Shared On Export [Import(RequiredCreationPolicy=CreationPolicy.NonShared)] [Import(RequiredCreationPolicy=CreationPolicy.Shared)] On Import