TCP Fast Open - WeiFei365/shadowsocks GitHub Wiki

If both of your server and client are deployed on Linux 3.7.1 or higher, you can turn on fast_open for lower latency.

First set fast_open to true in your config.json.

Then turn on fast open on your OS temporarily:

echo 3 > /proc/sys/net/ipv4/tcp_fastopen

To turn on fast open permanently, see Optimizing Shadowsocks.

Notice: only some versions support this feature.