gistfile1.js

if (Meteor.isServer) {
    WebApp.connectHandlers.use("/test", function (req, res, next) {
        var data = '';
        req.on('data', function (chunk) {
            data += chunk;
        });
        req.on('end', Meteor.bindEnvironment(function () {
            var deserialized = JSON.parse(data);
            // Do your work here
            console.log(deserialized.d.length);
            res.end(data.length.toString());
        }))
    });
}

if (Meteor.isClient) {
    Meteor.startup(function () {
        var c = '          ';
        var d = '';
        for (var i = 0; i < Math.pow(10, 7) / 2; i++) {
            d += c + c;
        }
        HTTP.post('http://localhost:3000/test', {data: {d: d.slice('undefined'.length)}}, function (e, r) {
            console.log(e);
            console.log(r);
        });
    });
}