Network Tweaks

Pop this into your /etc/sysctl.conf and reboot

kern.ipc.somaxconn=512
net.inet.tcp.mssdflt=1460
net.inet.tcp.sendspace=98304
net.inet.tcp.recvspace=98304
kern.ipc.maxsockbuf=1048576
net.inet.udp.maxdgram=57344
net.inet.udp.recvspace=42080
net.local.stream.sendspace=98304
net.local.stream.recvspace=98304
net.inet.tcp.delayed_ack=0
net.inet.tcp.rfc1323=1
net.inet.tcp.rfc1644=1
net.inet.tcp.newreno=1

Via devroot

To initiate the changes into the kernel without a reboot, add the above to /etc/sysctl.conf then issue the following command string:

awk '{ if (!index($1, "#") && index($1, "=")) print $1 }' < /etc/sysctl.conf | while read
do
        sysctl -w ${REPLY}
done

If successful, you should see the following output from sysctl confirming the changes:

kern.ipc.somaxconn: 128 -> 512
net.inet.tcp.mssdflt: 512 -> 1460
net.inet.tcp.sendspace: 32768 -> 98304
net.inet.tcp.recvspace: 32768 -> 98304
kern.ipc.maxsockbuf: 262144 -> 1048576
net.inet.udp.maxdgram: 9216 -> 57344
net.inet.udp.recvspace: 42080 -> 42080
net.local.stream.sendspace: 8192 -> 98304
net.local.stream.recvspace: 8192 -> 98304
net.inet.tcp.delayed_ack: 3 -> 0
net.inet.tcp.rfc1323: 1 -> 1
net.inet.tcp.rfc1644: 0 -> 1
net.inet.tcp.newreno: 0 -> 1

(Taken directly from the applicable portion of /etc/rc, the primary boot script. While the above Apple command syntax does not really provide much safeguard, and there are more simple ways to apply the changes via command line, this is the way the ATV does it at every reboot and thus the way promoted here.)