Multiple Task.Run() & WaitAll()

Scenario:

From MSDN:

For I/O-bound code, you await an operation that returns a Task or Task<T> inside of an async method.

For CPU-bound code, you await an operation that is started on a background thread with the Task.Run method.

You can use Task.Run to move CPU-bound work to a background thread, but a background thread doesn't help with a process that's just waiting for results to become available.

Solution:

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    protected  void ProcessItems(Item[] item)
    {
        var tasks = item.Select(i =>
            Task.Run(() =>
            {
                var stopwatch = Stopwatch.StartNew();
                ProcessItemsAsync(d).Wait();
                stopwatch.Stop();
                    }));
        Task.WaitAll(tasks.ToArray());
    }