Polymer performance numbers bookmarklet

polymer-perf-bookmarklet.js

javascript:(function(){(function printStats(){var loadTimes=window.chrome.loadTimes();firstPaint=loadTimes.firstPaintTime*1000;firstPaintTime=firstPaint-(loadTimes.startLoadTime*1000);console.info('First paint took',firstPaintTime,'ms');console.info('Load took',performance.timing.loadEventStart-performance.timing.navigationStart,'ms');var instances=0;if(parseFloat(Polymer.version)<1){instances=[].slice.call(document.querySelectorAll('html /deep/ *')).filter(function(el){return el.localName.indexOf('-')!=-1||el.getAttribute('is');}).length;}else{instances=Polymer.telemetry.instanceCount;}console.info('Custom element instances:',instances);var reflectCount=0;if(Polymer.telemetry){console.info('=== Properties set to reflectToAttribute ===');Polymer.telemetry.registrations.forEach(function(el){for(var prop in el.properties){if(el.properties[prop].reflectToAttribute){console.log(el.is+'.'+prop);reflectCount++;}}});}else{console.info('=== Properties set to reflect ===');Polymer.elements.forEach(function(el){for(var prop in el.prototype.publish){var propVal=el.prototype.publish[prop];if(propVal&&propVal.reflect){console.log(el.name+'.'+prop);reflectCount++;}}});}console.info('Total properties set to reflectToAttribute:',reflectCount);var imports=document.querySelectorAll('link[rel="import"]');var table=[];var totalDuration=0;console.info('=== HTML Imports load times ===');[].forEach.call(imports,function(link){var entries=performance.getEntriesByName(link.href);entries.forEach(function(e){table.push({url:e.name,ms:e.duration});totalDuration+=e.duration;});});console.log(imports.length+' imports loaded from the main page. Total time: '+totalDuration+'ms');console.table(table);})();})();

polymer-perf.js

(function printStats() {
  // First paint
  var loadTimes = window.chrome.loadTimes();
  firstPaint = loadTimes.firstPaintTime * 1000;
  firstPaintTime = firstPaint - (loadTimes.startLoadTime * 1000);
  console.info('First paint took', firstPaintTime, 'ms');
  
  // Page load.
  console.info('Load took', performance.timing.loadEventStart - performance.timing.navigationStart, 'ms');
  
  // # of custom element instances
  var instances = 0;
  if (parseFloat(Polymer.version) < 1) { // Polymer 0.5.
    instances = Array.from(document.querySelectorAll('html /deep/ *')).filter(el => {
      const isAttr = el.getAttribute('is');
      return el.localName.includes('-') || isAttr && isAttr.includes('-');
    }).length;
  } else {
    instances = Polymer.telemetry.instanceCount;
  }
  console.info('Custom element instances:', instances);
  
  // Properties being reflected to attributes.
  var reflectCount = 0;
  if (Polymer.telemetry) {
    console.info('=== Properties set to reflectToAttribute ===');
    Polymer.telemetry.registrations.forEach(function(el) {
      for (var prop in el.properties) { 
        if (el.properties[prop].reflectToAttribute) {
          console.log(el.is + '.' + prop);
          reflectCount++;
        }
      }
    });
  } else { // 0.5 code
    console.info('=== Properties set to reflect ===');
    Polymer.elements.forEach(function(el) {
      for (var prop in el.prototype.publish) { 
        var propVal = el.prototype.publish[prop];
        if (propVal && propVal.reflect) {
          console.log(el.name + '.' + prop);
          reflectCount++;
        }
      }
    });
  }
  console.info('Total properties set to reflectToAttribute:', reflectCount);
  
  // Main page imports perf.
  var imports = document.querySelectorAll('link[rel="import"]');
  var table = [];
  var totalDuration = 0;
  console.info('=== HTML Imports load times ===');
  [].forEach.call(imports, function(link) {
    var entries = performance.getEntriesByName(link.href);
    entries.forEach(function(e) {
      table.push({url: e.name, ms: e.duration});
      totalDuration += e.duration;
    });
  });
  console.log(imports.length + ' imports loaded from the main page. Total time: ' + totalDuration + 'ms');
  console.table(table);
  
})();

Is reflectToAttribute particularly resource intensive? How does it affect performance?

@ebidel any reason the times would be negative?

@ebidel what do you think the two questions above? I also have questions about these two issues.