Question

I need to call a couple of methods asynchronously with different priorities.

My first idea was to use the ThreadPool and change the priority of the Thread like this:

static void Run() {   ThreadPool.QueueUserWorkItem(new WaitCallback(SomeMethod)); }  static void SomeMethod(object o) {   Thread.CurrentThread.Priority = ThreadPriority.BelowNormal; // is this ok?   // do some work here } 

Does that work or what do you recommend?

Answer 1

According to http://msdn.microsoft.com/en-us/library/0ka9477y.aspx, it won’t work if you are targeting 2.0, it alludes to there being some differences in 3.5 but doesn’t specifically mention priority:

When Not to Use Thread Pool Threads

There are several scenarios in which it is appropriate to create and manage your own threads instead of using thread pool threads:

• You require a foreground thread.

• You require a thread to have a particular priority.

• You have tasks that cause the thread to block for long periods of time. The thread pool has a maximum number of threads, so a large number of blocked thread pool threads might prevent tasks from starting.

• You need to place threads into a single-threaded apartment. All ThreadPool threads are in the multithreaded apartment.

• You need to have a stable identity associated with the thread, or to dedicate a thread to a task.

You’ll likely need to come up with your own implementation, and handle creation of Threads directly.

Question: What are you trying to achieve do you have a set of tasks to be processed and you want high priority tasks to happen first, and lower ones to happen later; or do you actually want Threads of differing priority?