Using ThreadPool With Callbacks

Question

I am using ThreadPool to handle every connected Socket in my Socket Server separately. However i wonder if the callback of BeginReceive also gets execute inside the ThreadPool

ThreadPool.QueueUserWorkItem(o =>
{
    if (ClientExchange != null && ClientExchange(asynchronousState)) {
        if (ClientConnect != null) {
            ClientConnect(asynchronousState);
        }
    }
    ConnectedClients.Add(ipEndPoint, socket);
    socket.BeginReceive(asynchronousState.Buffer, 0, asynchronousState.Buffer.Length, SocketFlags.None, HandleAsyncReceive, asynchronousState);
});

Does the HandleAsyncReceive callback gets also executed in the new Thread (which was grabbed by the ThreadPool) ?

What did you see when you printed `Thread.CurrentThread.ManagedThreadId` ? — L.B, Mar 06 '14 at 19:35
You don't need to use pool threads explicitly. You can do the processing on the same thread your `BeginReceive`-callback gets invoked on, it's going to be a random but different pool thread. Check the comments to this answer: http://stackoverflow.com/a/22017432/1768303 — noseratio, Mar 06 '14 at 22:37

usr · Answer 1 · 2014-03-06T19:53:39.263

1

Callbacks for async IO are called on thread-pool threads.

Thread-pool threads are never reserved for any specific purpose. Every work item can see a totally different thread-id. Or all work items could see the same thread-id. Nothing is guaranteed.

Normally, you don't rely on the exact thread that your code will run on. This is usually a bug. You should not care about this (and I'm unclear why you do).

what i want to do is handle every accepted Socket on a different thread

That does not make sense in the context of async IO. Async IO is thread-less. While an IO is running there is no thread in use for it.

edited Mar 06 '14 at 19:53

answered Mar 06 '14 at 19:39

usr

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i don't wanna do the callbacks on new threads, what i want to do is handle every accepted Socket on a different thread (including all of it's callbacks) – Roman Ratskey Mar 06 '14 at 19:40
see my updated topic for another strange manner (see the comments inside the code) – Roman Ratskey Mar 06 '14 at 19:40
yea that is useful however i want to handle every connection on a separate thread because inside my custom classbacks OnClientConnect and OnClientExchange etc... i am using synchronous code for some operations and when i do so without the ThreadPool i get all the server as well as the console application to hang up idk why ? – Roman Ratskey Mar 06 '14 at 20:03
I have no idea and it seems to be out of scope for this question. You can mix sync and async IO. That should work. The bug is something else. Open a new question and post code. – usr Mar 07 '14 at 11:47

Using ThreadPool With Callbacks

1 Answers1