Max # of worker threads and Begin Invoke

All,

From what I've read, the CLR gives each App Domain a thread pool of 25
threads, and once this pool is exhausted then any new threads created with
BeginInvoke will block until the pool frees up another thread. Am I right on
that?

I did a little test where I went into a loop and attempted to spawn 50 new
worker threads with a call to BeginInvoke that used an asynchronous
callback. I expected it to launch 24 threads, then block for a while until
the threads completed. But instead, it never blocked and completed the loop
immediately. Here is a snippet of the code:

for (int i=0;i<50;i++)
{
WorkerThread_De legate dlgt = new
WorkerThread_De legate(Class2.W orkerThread);
IAsyncResult ar = dlgt.BeginInvok e(new AsyncCallback(C allback),dlgt );
}
Console.WriteLi ne("** FINISHED SPAWNING THREADS **");

(The Class2.WorkerTh read simply causes the thread to sleep for 10 seconds.)

So when I run this, it immediately finishes the loop and outputs the line
about finished spawning threads. Why didn't it block after creating the
first 24 threads? Is it because I am using an asynchronous callback?

Thanks for any info. I've read what I've seen on MSDN, but either I missed
something or it just isn't sinking in because I don't fully understand this
behavior.

Mark