Question

I have question on controlling the amount of concurrent threads I want running. Let me explain with what I currently do: For example

 var myItems = getItems(); // is just some generic list

 // cycle through the mails, picking 10 at a time
 int index = 0;
 int itemsToTake = myItems.Count >= 10 ? 10 : myItems.Count;
 while (index < myItems.Count)
 {
     var itemRange = myItems.GetRange(index, itemsToTake);
     AutoResetEvent[] handles = new AutoResetEvent[itemsToTake];

     for (int i = 0; i < itemRange.Count; i++)
     {
         var item = itemRange[i];
         handles[i] = new AutoResetEvent(false);

         // set up the thread
         ThreadPool.QueueUserWorkItem(processItems, new Item_Thread(handles[i], item));
     }

    // wait for all the threads to finish
    WaitHandle.WaitAll(handles);

    // update the index
    index += itemsToTake;
    // make sure that the next batch of items to get is within range
    itemsToTake = (itemsToTake + index < myItems.Count) ? itemsToTake : myItems.Count -index;

This is a path that I currently take. However I do not like it at all. I know I can ‘manage’ the thread pool itself, but I have heard it is not advisable to do so. So what is the alternative? The semaphore class?

Thanks.

Answer 1

Don’t use THE treadpool, get another one (just look for google, there are half a dozen implementations out) and manage that yourself.

Managing THE treadpool is not advisable as a lot of internal workings may go ther, managing your OWN threadpool instance is totally ok.