Thanks to work done by Netflix and NGINX, a new, drop-in-replacement sendfile syscall has been written for FreeBSD that is much faster.

As of today the latest FreeBSD SVN kernel code has the new sendfile() syscall developed by NGINX and Netflix over the past few years. This sendfile is already used by Netflix " to send their multiple tens of gigabits of data per second."

This new sendfile syscall from sending a file to a socket supports asynchronous I/O, completely non-blocking, all-around much faster, supports extra flags, and will work with all existing applications.

More details via the SVN commit to FreeBSD.