Is it safe to wrap NetworkStream with BufferedStream for async reading?

Question

I'm using NetworkStream.BeginRead to read asynchronously from a Socket.

But it is much faster if you actually wrap the network stream with a BufferedStream.

My question: NetworkStream.BeginRead internally invokes to Socket.BeginReceive and the whole stack of async IO (CompletionPorts on Windows and so on). Does the same happen when BufferedStream is in the middle?

Answer 1

BufferedStream does not support efficient async IO. It uses the default implementation inherited from the Stream class. It will issue synchronous IOs on the thread-pool. So you won't get IO completion ports doing that. You need to do this work yourself. If you are using C# 5 you can nearly reuse BufferedStream's implementation and try to slap async and awaits on it.