What is the optimal size of a UDP packet for maximum throughput?

Question

I need to send packets from one host to another over a potentially lossy network. In order to minimize packet latency, I\'m not considering TCP/IP. But, I w

Answer 1

Well, I've got a non-MTU answer for you. Using a connected UDP socket should speed things up for you. There are two reasons to call connect on your UDP socket. The first is efficiency. When you call sendto on an unconnected UDP socket what happens is that the kernel temporarily connects the socket, sends the data and then disconnects it. I read about a study indicating that this takes up nearly 30% of processing time when sending. The other reason to call connect is so that you can get ICMP error messages. On an unconnected UDP socket the kernel doesn't know what application to deliver ICMP errors to and so they just get discarded.