Networking Method

Question

Hey guys, Iv'e noticed that when I send a complete packet (collect it's data in a buffer and send) it is much slower than sending the packet byte by byte. Will it be okay if I make an online game using this method?

Answer 1

That sounds bizarre. There is much more overhead in sending data byte by byte. Your transport headers will far outweigh the payload! Not to mention O(n) send calls (where n is the number of bytes).

You're doing something wrong if that's what you experience.

Answer 2

I think you need to define what are your measurement points (what exactly are you measuring). By the way is this TCP or UDP?

Anyway Winsock has its own internal buffers that you can modify by calls to setsockopt.

Answer 3

What I didn't really measure anything, I'm pretty sure it has something to do with sending data and not collecting it.. I'm using C# for server-side and C++ for client side, in the server side I wrapped the socket with a BinaryWriter and BinaryReader, and in the client I just used send and recv to send every byte.

Answer 4

Sounds like a naggling-related problem.

You have to disable naggling for latency-demanding applications. (See setsockopt, TCP_NODELAY).

Explanation:

TCP stack behaves differently for small chunks, trying to combine them in bizare ways on the way to IP datagrams. This is a performance optimization suggested by J.Nagle (hence nagling). Keep in mind that enabling NODELAY will make every send() call a kernel-mode transition, so you may wish to pack streams into chunks yourself by means of memory copying, before feeding them into send() if performance is an issue for what you are doing.