A friend of mine was complaining that he could only upload a file to my server at 2Mbytes/sec with his FIOS link at home. Some people have interesting "problems".
Anyway, I send him my
/etc/sysctl.conf that I have on my Mac for quite some time without any problems, and with significant gains in network performance on my local LAN (specially for other computers with Gigabit ethernet).
net.inet.tcp.mssdflt=1440 kern.ipc.maxsockbuf=800000 net.inet.tcp.sendspace=400000 net.inet.tcp.recvspace=400000
Stick those lines in your
/etc/sysctl.conf and they will be active every time your Mac reboots. Make sure you place them on all your Macs. To activate them right now, run this:
sudo sysctl -w net.inet.tcp.mssdflt=1440 sudo sysctl -w kern.ipc.maxsockbuf=800000 sudo sysctl -w net.inet.tcp.sendspace=400000 sudo sysctl -w net.inet.tcp.recvspace=400000
You should see network a better network throughput immediately.
There is a fifth setting:
but I admit not to fully understand the implications of his use. Apparently without it, the
recvspace settings would not work, but my tests tell me the oposite. I'll update this when I do know if/when to use the one.
For reference, a local FTP transfer to a 100Mbit server was not using all of the bandwidth. With just the first line, I was able to saturate the server link. With all the lines, over a gigabit ethernet link, I was able to reach 35Mbytes/sec between two Macs. Without: a meager 6Mbyte/sec.
All the gory details are available in a study by the Pittsburgh Computing Center.
Update: sorry, miss-typed the values, remove the extra zero.