不同时间的并行任务执行

Question

我有一个控制台应用程序，它可以并行执行几个任务。就我而言，重要的部分是我希望任务同时完成。我知道每项任务需要多长时间。因此，我们的想法是以某种方式延迟 Parallel.ForEach 中的每项任务，每个任务都有自定义时间延迟，以便它们都同时完成，最后所有任务将与花费最多的任务大致同时完成时间.

示例：

interface IService
{
    void DoWork();
}

class Program
{
    static void Main(string[] args)
    {
        var services = new List<IService>();
        services.Add(new ServiceA());//Takes 500ms to DoWork()
        services.Add(new ServiceB());//Takes 1000ms to DoWork()
        services.Add(new ServiceC());//Takes 5000ms to DoWork()

        Parallel.ForEach(services, z =>
        {
            Stopwatch sw = new Stopwatch();
            sw.Start();
            z.DoWork();
            Console.WriteLine($"Ready for {sw.Elapsed}");
        });
    }
}

输出：

Ready for 00:00:00.5006837
Ready for 00:00:01.0002284
Ready for 00:00:05.0010202
Press any key to continue . . .

如何修改代码使输出如下所示：

Ready for 00:00:05.5006837
Ready for 00:00:05.0002284
Ready for 00:00:05.0010202
Press any key to continue . . .

我想最明显的解决方案是在循环中区分哪个服务是 z 并在调用 z.DoWork() 之前添加自定义 Thread.Sleep，但我正在寻找更智能的解决方案。

Answer 1

感谢您的帮助！所以这就是我想要实现的。所有服务同时完成它们的工作。这是正确的做法吗？

class Program
{
    static void Main(string[] args)
    {
        ServiceA a = new ServiceA();
        ServiceB b = new ServiceB();
        ServiceC c = new ServiceC();

        int maxDelay = 3000;
        var sw = new Stopwatch();
        sw.Start();

        Task taskA = Task.Delay(maxDelay - a.ResponseTime).ContinueWith(x =>
          {
              a.DoWork();
              Console.WriteLine($"taskA ready for {sw.Elapsed}");
          });

        Task taskB = Task.Delay(maxDelay - b.ResponseTime).ContinueWith(x =>
          {
              b.DoWork();
              Console.WriteLine($"taskB ready for {sw.Elapsed}");
          });

        Task taskC = Task.Delay(maxDelay - c.ResponseTime).ContinueWith(x =>
        {
            c.DoWork();
            Console.WriteLine($"taskC ready for {sw.Elapsed}");
        });

        taskA.Wait();
        taskB.Wait();
        taskC.Wait();

        Console.WriteLine(sw.Elapsed);
    }
}

class ServiceA
{
    public int ResponseTime { get => 500; }
    public void DoWork() => Thread.Sleep(500);
}

class ServiceB
{
    public int ResponseTime { get => 1000; }
    public void DoWork() => Thread.Sleep(1000);
}

class ServiceC
{
    public int ResponseTime { get => 3000; }
    public void DoWork() => Thread.Sleep(3000);
}

输出：

taskA ready for 00:00:03.0084344
taskC ready for 00:00:03.0102184
taskB ready for 00:00:03.0102588

*Thread.Sleep(x)代表一些耗时操作。

不同时间的并行任务执行

Parallel task execution at different time

.net

c#

multithreading

task-parallel-library