Haven't heard of TCP_CORK, very interesting.

For people who don't feel like googling it:

1. You TCP_CORK a socket

2. You put data into it and the kernel buffers it

3. If you uncork the socket, or if the buffer hits MSS, the kernel sends the packet

Basically, the kernel waits until it has a full packet worth of data, or until you say you don't have any more data to send, and then it sends. Sort of an extreme TCP_YESDELAY.

See https://catonmat.net/tcp-cork for where I learned it all from.