Download - Tpl DataFlow
Dmitri [email protected]
A publishes an eventB subscribes to the eventIf lifetime of B < lifetime of A
We can get a memory leak
Weak event pattern
Library for composing async/event-based programsEvent subscription wrapped as IDisposable
Lets you manually unsubscribeUnsubscription automatic when source runs out of data to supply
Declarative subscriptionsPub/sub mechanism
Objects not aware of each otherTypically built on top of a DI containerEach component references the broker
ErlangF# MailboxProcessorAxum (dead)Task Parallel Library (TPL) DataFlow
A library approach
Fine-grainedData-level (SIMD) – not in .NETAutoparallelization
Coarse-grainedUsing threadsWeird synchronization primitives (e.g. Pulse&Wait)TPL DataFlow
A directed graph of dataMessage passingBufferingParallel executionDependency management
Pipeline
Network
read process process write
process
read
process
collate writeprepare
OutputPropagateInput
Read stock market data
Calculate indices
Render to screen
Save to DB
Filter Save to DB
ISourceBlock<T>Source of data; read
ITargetBlock<T>Where you write the data to
IPropagatorBlock<TIn,TOut>Propagator; performs data processing/filtering
As with Rx, ready-made implementations provided
TransformBlockTransforms dataAlso: TransformManyBlock
ActionBlockProcesses the data
Post()Sends a piece of data to the block for processing
LinkTo ()Links a block with the next block in the graphTakes an optional predicateReturns an Idisposable
CancelationTokenSource if you change your mind
Basic block processing
BatchBlock<T>Combines sets of blocks into an array
JoinBlock<2> and <3>Collects 2 or 3 inputs into a Tuple<2/3>
BatchJoinBlockMerger of the aboveCollects Tuple<IList<T>,…>
Provides a data storage bufferCan be used synchronously
block.Post()block.Receive()
or asynchronouslyawait block.SendAsync()Await block.ReceiveAsync()
Grouping Blocks
Not a competitor to Rx or TPL itselfCourse-grained parallelization/sequencing mechanism‘Cheap’ multithreading
Questions?
Конференция по .NET технологиям4 апреля 2014, ПетроКонгрессhttp://dotnext.ruПредлагайте доклады
