raw socket bypassing tcp/ip headers

Question

I have a 2 programs that are communicating via sockets on the same computer. Currently 1.6 million bytes is taking about 7 seconds to transfer using TCP/IP. I need to make it fast.

If I use a raw socket instead, and ignore the TCP/IP headers, then this should increase the speed? Is there anything else I can do to increase speed? Is the SOCKET_RAW option a straight copy or does it do anything else?

Answer 1

1.6MB shouldn't take 7 seconds using "normal" TCP/IP - certainly not on the same machine! That suggests you've got inefficient code somewhere. I'd address that before trying to do anything "special" in terms of the networking.

EDIT: I've just written a short C# program on a netbook, and that transfers 2MB (generating random data as it goes) in 279ms. That's with no optimization. Unless you're running on a machine from the 1980s, you should definitely be getting better performance than that...

Answer 2

尝试改用Unix域套接字。

Answer 3

To get that poor of performance, you are doing something very inefficient. Perhaps the i/o operations are single byte?

Changing to raw sockets is a bad idea. To get reliable communication, you'd then have to add some sort of data checking, sequencing, etc., etc.: everything that TCP does for reliability.

If the purpose is to transfer data from one process to another on the same machine, use shared memory and a mutex to synchronize access. Of course this is not a good solution if the programs will eventually have to run on separate machines.

Answer 4

No, using raw IP sockets is definitely not a good idea. Using a unix-domain socket might be marginally more efficient, but I doubt it's going to solve your problem. You clearly have another problem. Perhaps it is your application-level protocol which is inefficient?