Queue<T> thread-safety: one writer, one reader

Question

I've got a Queue<T> _q = new Queue<T>();

There's always only one thread populating it: _q.Enqueue(msg);

There's always only one thread consuming it: _q.Dequeue();

I want to be lock-free in both threads. Performance is important but safety is on the first place.

Do I need making _q a ConcurrentQueue<T>?

UPD That can be important: I do not need to be sure that reading thread will successfully dequeue item immediatly after writing thread enqueues it. If a few false dequeues will be taken - that's ok.

Answer 1

Do I need making _q a ConcurrentQueue

Yes. A Queue is not thread safe.

Answer 2

Here you can find a lock free queue: Lockfreie threadsichere Queue - don't be afraid of the site being in german - the code should speak for itself. Furthermore, there's another, little more in-depth article at Writing Lock-Free Code: A Corrected Queue