Performance test with node.js

app.js

var request = require('request');
var async = require('async');

var url = "...";
var payload = "...";

var calls = [];
var clients = 100;
var callsPerClient = 20;
var thinkTime = 0;
var totalRequests = callsPerClient * clients;

var testStartTime = (new Date()).getTime();

for ( var i = 0; i < totalRequests; i++ ) {
  calls.push(runCall);
}

async.parallelLimit(calls, clients, function(err) {
  console.log('complete', err);
  var testEndTime = (new Date()).getTime();
  var totalTime = (testEndTime - testStartTime) / 1000;
  var requestsPerSecond = Math.round(totalRequests / totalTime);
  console.log('completed ' + totalRequests + ' in ' + totalTime + 's, requests/sec=' + requestsPerSecond);
});

function runCall(callback) {
  var startTime = (new Date()).getTime();
  var options = {
    method:'POST',
    body: payload,
    url: url,
    timeout: 30000,
    strictSSL: false,
    headers: {
      'Content-Type': 'text/xml;charset=UTF-8',
      'User-Agent': 'Connors NodeJS Perf Tester'
    }
  };

  request(options, function(error,response,body) {
    var endTime = (new Date()).getTime();
    //console.log(response);
    console.log("Time=" + (endTime - startTime) + "ms Err=" + error, "Response Code=" + response.statusCode + " Response Len=" + body.length);
    setTimeout(function() {
      callback();
    }, thinkTime);
  });
}