debug chrome

 /Applications/Google\ Chrome\ Canary.app/Contents/MacOS/Google\ Chrome\ Canary --enable-logging --v=1 --enable-memory-info --js-flags="--expose-gc" --enable-precise-memory-info
 
 tail -f ~/Library/Application\ Support/Google/Chrome\ Canary/chrome_debug.log

start-app.js

/* exported
  customHelpers
*/

import Ember from "ember";
import Application from "../../app";
import config from "../../config/environment";
import customHelpers from "./app-custom-test-helpers";

// https://github.com/paulirish/memory-stats.js/blob/master/memory-stats.js
let sizes = ["Bytes", "KB", "MB", "GB", "TB"];
let precision;
let i;
function bytesToSize( bytes, nFractDigit ) {
  let gc = false;
	if (bytes === 0) {
    return 0;
  }
  if(bytes < 0) {
    bytes = Math.abs(bytes);
    gc = true;
  }

	nFractDigit	= nFractDigit !== undefined ? nFractDigit : 0;
	precision = Math.pow(10, nFractDigit);
	i = Math.floor(Math.log(bytes) / Math.log(1024));
  let result = Math.round(bytes*precision / Math.pow(1024, i))/precision;
  if(gc) {
    result = result * -1;
  }
  return result;
}

window._profiling = window._profiling || {tests:[], lastUsedHeap:0, delta:0};

export default function startApp(attrs) {
  window._profiling.started = window._profiling.started || moment(QUnit.config.started);

  let testName = QUnit.config.current.module.name;
  let testId = QUnit.config.current.testId;
  let testModule = testName+testId;

  console.group(testModule);
  console.timeStamp(testModule, "startApp start");

  let formattedHeap = bytesToSize(window._profiling.lastUsedHeap, 2);
  let formattedDelta = bytesToSize(window._profiling.delta, 2);

  if(window.gc) {
    window.gc();
    window._profiling.delta = window.performance.memory.usedJSHeapSize - window._profiling.lastUsedHeap;
    window._profiling.lastUsedHeap = window.performance.memory.usedJSHeapSize;
    console.log(testModule, "heap: ", formattedHeap);
    console.log(testModule, "delta: ", formattedDelta);
  }

  let testStart = moment(QUnit.config.current.started);
  let timePassed = testStart.diff(window._profiling.started, "seconds");
  console.log(testModule, "# seconds:", timePassed);
  console.log(testModule, "# tests:", QUnit.config.current.module.tests.length);

  window._profiling.tests.push({
    id: testId,
    name: testName,
    heapDelta: formattedDelta,
    heapSize: formattedHeap
  });

  let application;

  let attributes = Ember.merge({}, config.APP);
  attributes = Ember.merge(attributes, attrs); // use defaults, but you can override;

  Ember.run(() => {
    application = Application.create(attributes);
    application.setupForTesting();
    application.injectTestHelpers();
  });
  console.groupEnd();
  return application;
}

export default function startApp(attrs) {
var application;

window.gc();
console.log("beforeStart", window.performance.memory.usedJSHeapSize);
var attributes = Ember.merge({}, config.APP);
attributes = Ember.merge(attributes, attrs); // use defaults, but you can override;

Ember.run(function() {
application = Application.create(attributes);
application.setupForTesting();
application.injectTestHelpers();
});

window.gc();
console.log("afterStart", window.performance.memory.usedJSHeapSize);
return application;
}

import Ember from "ember";

export default function destroyApp(application) {
window.gc();
console.log("beforeDestroy", window.performance.memory.usedJSHeapSize);
Ember.run(application, "destroy");

window.gc();
console.log("afterDestroy", window.performance.memory.usedJSHeapSize);
}