setwindow is an application to set the tcp window size on a machine. You can set the sender and receiver windows independently.
Src is /usr/src/setwindow on topsecret and the executable is in /usr/home/bin.
setwindow can be found in /usr/home/bin/setwindow on FreeBSD machines.
Running setwindow is simple:
setwindow [-S send_window] [-R recv_window]
This is just an executable to do the following sysctl commands:
sysctl -w net.inet.tcp.sendspace = send_window or sysctl -w net.inet.tcp.recvspace = recv_windowNote: Even though you've set the TCP window size, you might still need to use setsockopt() to set the send (SO_SNDBUF) and receive (SO_RCVBUF) socket buffer sizes.
Also look at Setting socket buffer sizes.