WebSockets very, very slow when sending ~1800 characters

Okay, so I've opted for the "net" module instead as a socket server. It's much, much, much faster! I can easily do 50ms now without issues.

var esp8266 = require("ESP8266");

function onInit() {
  var ssid = "SSID";
  var wifiOpts = {
    password: "PASSWORD"
  };
  var wifi = require("Wifi");
  wifi.connect(ssid, wifiOpts, function(err) {
    console.log("connected? err=", err, "info=", wifi.getIP());
    require("net").connect({host: "192.168.1.209", port: 8001}, function(socket) {
      console.log("Connected");

      var arr = "";
      socket.on("data", function(data) {
        arr += data;
        if(arr.slice(-2) == "]]") {
          data = JSON.parse(arr);
          esp8266.neopixelWrite(NodeMCU.D2, data);
          arr = "";
        }
      });
    });
  });
}

save();

I had to hack it up a bit, because I send so many characters. I saw that the socket.on("data") got hit way too many times. Apparently it either receives or sends in chunks of ~260 characters, so I simply add those to a string, check if the last two characters are ]] (meaning my 2D array is complete) and then JSON.parse() it.

Works amazingly fast!