delayed_ack mac file transfer super slow

sudo sysctl -a net.inet.tcp.delayed_ack
out of the box will return:
net.inet.tcp.delayed_ack: 3

recommended from article:
sudo sysctl -w net.inet.tcp.delayed_ack=2

I have not ran any test, but if the computer is strictly being used in an office environment. Disabling delayed ack all together may not be a bad idea.
sudo sysctl - w net.inet.tcp.delayed_ack=0

for changes to persist after reboot save to /etc/sysctl.conf

reference:
http://www.shabangs.net/osx/speed-up-macos-x-file-transferring-over-network/
http://www.stuartcheshire.org/papers/NagleDelayedAck/
http://en.wikipedia.org/wiki/TCP_delayed_acknowledgment