Microsoft's CCR vs Task Parallel Library

问题:

Microsoft has at least two different approches to improved support for concurrent operations.

1) Is the Concurrency Coordination Runtime (CCR) which is part of Microsoft Robotics Studio and CCR & DSS Toolkit

2) Task Paralell Library (TPL) (Part of .NET 4.0 and now in Beta 1 release)

I would like to know if anyone has experience with these two different pieces of software and would compare and contrast them?

回答1:

By and large, both frameworks have complementary but different goals.

The CCR offers primitives for coordination of concurrent processes. Coordination is the glue that makes a bunch of processes work as a whole - so the CCR offers primitives for exchanging messages through so called channels. Processes can wait for a message to arrive on a channel, or a number of channels, or any one of a number of channels and so forth. This is a particular paradigm for coordination of concurrent processes that works well. Note also that is it not free - you have to buy if from Microsoft separately.

The TPL offers primitives and infrastructure to parallellize computations or algorithms semi-automatically. One of the most obvious primitives there is the parallel for loop - looks sort of like a for loop but tries to execute the loop in parallel.

So, if you have a bunch of process that you'd like to coordinate on a higher level than using shared state and locks, use the CCR. If you have a computation-intensive process that you'd like to run efficiently on a multi-core machine, use the TPL.

回答2:

It's not an either/or scenario. The CCR is a library that supports certain programming patterns. You can intermix CCR and TPL code like this, here is a Parallel.For inside of a Receive delegate:

using System;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.Ccr.Core;

namespace Demo
{
    public class Program
    {
        public static void Main(string[] args)
        {
            Dispatcher dispatcher = new Dispatcher();
            DispatcherQueue taskQueue = new DispatcherQueue("Demo", dispatcher);
            Port<int> portInt = new Port<int>();
            portInt.Post(Int32.Parse(args[0]));

            Arbiter.Activate(
                taskQueue,
                portInt.Receive(delegate(int count)
                {
                    Parallel.For(0, count, i =>
                    {
                        Console.Write(i.ToString() + " ");
                    });
                }
            ));
        }
    }
}