Plots: make measure script more flexible (CLI args)

.gitignore

@@ -47,4 +47,4 @@ lighthouse-cli/types/*.map
 lighthouse-core/report/partials/templates/
 lighthouse-core/report/templates/*.js
 
-plots/out/
+plots/out**

plots/ab-screenshot/analyze.js

@@ -22,6 +22,8 @@ const path = require('path');
 const opn = require('opn');
 const args = require('yargs').argv;
 
+const runs = args['runs'] || 1;
+
 const Metrics = require('../../lighthouse-core/lib/traces/pwmetrics-events');
 
 const constants = require('../constants');
@@ -84,25 +86,58 @@ function aggregate(outPathA, outPathB) {
     if (!utils.isDir(sitePathB)) {
       return;
     }
-    const siteScreenshotsComparison = {
-      siteName: siteDir,
-      runA: analyzeSingleRunScreenshots(sitePathA),
-      runB: analyzeSingleRunScreenshots(sitePathB)
-    };
-    results.push(siteScreenshotsComparison);
+
+    for (let i = 0; i < runs; i++) {
+      const runDirA = getRunDir(sitePathA, i);
+      const runDirB = getRunDir(sitePathB, i);
+
+      const runPathA = path.resolve(sitePathA, runDirA);
+      const runPathB = path.resolve(sitePathB, runDirB);
+
+      const lighthouseFileA = path.resolve(runPathA, constants.LIGHTHOUSE_RESULTS_FILENAME);
+      const lighthouseFileB = path.resolve(runPathB, constants.LIGHTHOUSE_RESULTS_FILENAME);
+
+      if (!utils.isFile(lighthouseFileA) || !utils.isFile(lighthouseFileB)) {
+        continue;
+      }
+
+      const siteScreenshotsComparison = {
+        siteName: `${siteDir} runA: ${runDirA} runB: ${runDirB}`,
+        runA: analyzeSingleRunScreenshots(runPathA),
+        runB: analyzeSingleRunScreenshots(runPathB),
+      };
+      results.push(siteScreenshotsComparison);
+    }
   });
 
   return results;
 }
 
 /**
- * Analyzes the screenshots for the first run of a particular site.
  * @param {string} sitePath
+ * @param {number} runIndex
+ * @return {string}
+ */
+function getRunDir(sitePath, runIndex) {
+  return sortAndFilterRunFolders(fs.readdirSync(sitePath))[runIndex];
+}
+
+/**
+ * @param {!Array<string>} folders
+ * @return {!Array<string>}
+ */
+function sortAndFilterRunFolders(folders) {
+  return folders
+    .filter(folder => folder !== '.DS_Store')
+    .sort((a, b) => Number(a) - Number(b));
+}
+
+/**
+ * Analyzes the screenshots for the first run of a particular site.
+ * @param {string} runPath
  * @return {!SingleRunScreenshots}
  */
-function analyzeSingleRunScreenshots(sitePath) {
-  const runDir = sortAndFilterRunFolders(fs.readdirSync(sitePath))[0];
-  const runPath = path.resolve(sitePath, runDir);
+function analyzeSingleRunScreenshots(runPath) {
   const lighthouseResultsPath = path.resolve(runPath, constants.LIGHTHOUSE_RESULTS_FILENAME);
   const lighthouseResults = JSON.parse(fs.readFileSync(lighthouseResultsPath));
 
@@ -152,18 +187,6 @@ function analyzeSingleRunScreenshots(sitePath) {
   }
 }
 
-/**
- * @param {!Array<string>} folders
- * @return {!Array<string>}
- */
-function sortAndFilterRunFolders(folders) {
-  return folders
-    .filter(folder => folder !== '.DS_Store')
-    .map(folder => Number(folder))
-    .sort((a, b) => a - b)
-    .map(folder => folder.toString());
-}
-
 /**
  * Marks the first screenshot that happens after a particular perf timing.
  * @param {SingleRunScreenshots} results

plots/measure.js

@@ -17,11 +17,39 @@
 'use strict';
 
 /* eslint-disable no-console */
-
+const fs = require('fs');
 const path = require('path');
 const parseURL = require('url').parse;
 
 const mkdirp = require('mkdirp');
+const args = require('yargs')
+  .wrap(Math.min(process.stdout.columns, 120))
+  .help('help')
+  .usage('node $0 [options]')
+  .example('node $0 -n 3 --sites-path ./sample-sites.json')
+  .example('node $0 --site https://google.com/')
+  .example('node $0 --subset')
+  .describe({
+    'n': 'Number of runs per site',
+    'reuse-chrome': 'Reuse the same Chrome instance across all site runs',
+    'keep-first-run': 'If you use --reuse-chrome, by default the first run results are discarded',
+  })
+  .group(
+    ['disable-device-emulation', 'disable-cpu-throttling', 'disable-network-throttling'],
+    'Chrome DevTools settings:')
+  .boolean(['disable-device-emulation', 'disable-cpu-throttling', 'disable-network-throttling'])
+  .describe({
+    'disable-device-emulation': 'Disable Nexus 5X emulation',
+    'disable-cpu-throttling': 'Disable CPU throttling',
+    'disable-network-throttling': 'Disable network throttling',
+  })
+  .group(['sites-path', 'subset', 'site'], 'Options to specify sites:')
+  .describe({
+    'sites-path': 'Include relative path of a json file with urls to run',
+    'subset': 'Measure a subset of popular sites',
+    'site': 'Include a specific site url to run',
+  })
+  .argv;
 
 const constants = require('./constants.js');
 const utils = require('./utils.js');
@@ -31,135 +59,107 @@ const ChromeLauncher = require('../chrome-launcher/chrome-launcher.js');
 const Printer = require('../lighthouse-cli/printer');
 const assetSaver = require('../lighthouse-core/lib/asset-saver.js');
 
-const NUMBER_OF_RUNS = 20;
-
-const URLS = [
-  // Flagship sites
-  'https://nytimes.com',
-  'https://flipkart.com',
-  'http://www.espn.com/',
-  'https://www.washingtonpost.com/pwa/',
-
-  // TTI Tester sites
-  'https://housing.com/in/buy/real-estate-hyderabad',
-  'http://www.npr.org/',
-  'http://www.vevo.com/',
-  'https://weather.com/',
-  'https://www.nasa.gov/',
-  'https://vine.co/',
-  'http://www.booking.com/',
-  'http://www.thestar.com.my',
-  'http://www.58pic.com',
-  'http://www.dawn.com/',
-  'https://www.ebs.in/IPS/',
-
-  // Sourced from: https://en.wikipedia.org/wiki/List_of_most_popular_websites
-  // (http://www.alexa.com/topsites)
-  // Removed adult websites and duplicates (e.g. google int'l websites)
-  // Also removed sites that don't have significant index pages:
-  // "t.co", "popads.net", "onclickads.net", "microsoftonline.com", "onclckds.com", "cnzz.com",
-  // "live.com", "adf.ly", "googleusercontent.com",
-
-  'https://google.com',
-  'https://youtube.com',
-  'https://facebook.com',
-  'https://baidu.com',
-  'https://wikipedia.org',
-  'https://yahoo.com',
-  'https://amazon.com',
-  'http://www.qq.com/',
-  'https://taobao.com',
-  'https://vk.com',
-  'https://twitter.com',
-  'https://instagram.com',
-  'http://www.hao123.cn/',
-  'http://www.sohu.com/',
-  'https://sina.com.cn',
-  'https://reddit.com',
-  'https://linkedin.com',
-  'https://tmall.com',
-  'https://weibo.com',
-  'https://360.cn',
-  'https://yandex.ru',
-  'https://ebay.com',
-  'https://bing.com',
-  'https://msn.com',
-  'https://www.sogou.com/',
-  'https://wordpress.com',
-  'https://microsoft.com',
-  'https://tumblr.com',
-  'https://aliexpress.com',
-  'https://blogspot.com',
-  'https://netflix.com',
-  'https://ok.ru',
-  'https://stackoverflow.com',
-  'https://imgur.com',
-  'https://apple.com',
-  'http://www.naver.com/',
-  'https://mail.ru',
-  'http://www.imdb.com/',
-  'https://office.com',
-  'https://github.com',
-  'https://pinterest.com',
-  'https://paypal.com',
-  'http://www.tianya.cn/',
-  'https://diply.com',
-  'https://twitch.tv',
-  'https://adobe.com',
-  'https://wikia.com',
-  'https://coccoc.com',
-  'https://so.com',
-  'https://fc2.com',
-  'https://www.pixnet.net/',
-  'https://dropbox.com',
-  'https://zhihu.com',
-  'https://whatsapp.com',
-  'https://alibaba.com',
-  'https://ask.com',
-  'https://bbc.com'
-];
+const keepFirstRun = args['keep-first-run'] || !args['reuse-chrome'];
+const numberOfRuns = args['n'] || 3;
+
+function getUrls() {
+  if (args['site']) {
+    return [args['site']];
+  }
+
+  if (args['sites-path']) {
+    const sitesPath = path.resolve(__dirname, args['sites-path']);
+    if (path.extname(sitesPath) === '.json') {
+      return JSON.parse(fs.readFileSync(sitesPath, 'utf-8'));
+    } else if (path.extname(sitesPath) === '.js') {
+      return eval(fs.readFileSync(sitesPath, 'utf-8'));
+    } else {
+      throw new Error('Must pass a js or json file to --sites-path');
+    }
+  }
+
+  if (args['subset']) {
+    return eval(fs.readFileSync(path.resolve(__dirname, 'sites_subset.js'), 'utf-8'));
+  }
+
+  return eval(fs.readFileSync(path.resolve(__dirname, 'sites.js'), 'utf-8'));
+}
+
+const URLS = getUrls();
 
-/**
- * Launches Chrome once at the beginning, runs all the analysis,
- * and then kills Chrome.
- * TODO(chenwilliam): measure the overhead of starting chrome, if it's minimal
- * then open a fresh Chrome instance for each run.
- */
 function main() {
+  if (numberOfRuns === 1 && !keepFirstRun) {
+    console.log('ERROR: You are only doing one run and re-using chrome');
+    console.log('but did not specify --keep-first-run');
+    return;
+  }
+
   if (utils.isDir(constants.OUT_PATH)) {
     console.log('ERROR: Found output from previous run at: ', constants.OUT_PATH);
     console.log('Please run: npm run clean');
     return;
   }
 
-  return ChromeLauncher.launch({port: 9222})
-    .then(launcher => {
-      return runAnalysis()
+  if (args['reuse-chrome']) {
+    ChromeLauncher.launch().then(launcher => {
+      return runAnalysisWithExistingChromeInstances(launcher)
         .catch(err => console.error(err))
         .then(() => launcher.kill());
     });
+    return;
+  }
+  runAnalysisWithNewChromeInstances();
 }
 
 main();
 
 /**
+ * Launches a new Chrome instance for each site run.
+ * Returns a promise chain that analyzes all the sites n times.
+ * @return {!Promise}
+ */
+function runAnalysisWithNewChromeInstances() {
+  let promise = Promise.resolve();
+
+  for (let i = 0; i < numberOfRuns; i++) {
+    // Averages out any order-dependent effects such as memory pressure
+    utils.shuffle(URLS);
+
+    const id = i.toString();
+    const isFirstRun = i === 0;
+    const ignoreRun = keepFirstRun ? false : isFirstRun;
+    for (const url of URLS) {
+      promise = promise.then(() => {
+        return ChromeLauncher.launch().then(launcher => {
+          return singleRunAnalysis(url, id, launcher, {ignoreRun})
+            .catch(err => console.error(err))
+            .then(() => launcher.kill());
+        })
+        .catch(err => console.error(err));
+      });
+    }
+  }
+  return promise;
+}
+
+/**
+ * Reuses existing Chrome instance for all site runs.
  * Returns a promise chain that analyzes all the sites n times.
+ * @param {!Launcher} launcher
  * @return {!Promise}
  */
-function runAnalysis() {
+function runAnalysisWithExistingChromeInstances(launcher) {
   let promise = Promise.resolve();
 
-  // Running it n + 1 times because the first run is deliberately ignored
-  // because it has different perf characteristics from subsequent runs
-  // (e.g. DNS cache which can't be easily reset between runs)
-  for (let i = 0; i <= NUMBER_OF_RUNS; i++) {
+  for (let i = 0; i < numberOfRuns; i++) {
     // Averages out any order-dependent effects such as memory pressure
     utils.shuffle(URLS);
 
     const id = i.toString();
     const isFirstRun = i === 0;
+    const ignoreRun = keepFirstRun ? false : isFirstRun;
     for (const url of URLS) {
-      promise = promise.then(() => singleRunAnalysis(url, id, {ignoreRun: isFirstRun}));
+      promise = promise.then(() => singleRunAnalysis(url, id, launcher, {ignoreRun}));
     }
   }
   return promise;
@@ -169,10 +169,11 @@ function runAnalysis() {
  * Analyzes a site a single time using lighthouse.
  * @param {string} url
  * @param {string} id
+ * @param {!Launcher} launcher
  * @param {{ignoreRun: boolean}} options
  * @return {!Promise}
  */
-function singleRunAnalysis(url, id, {ignoreRun}) {
+function singleRunAnalysis(url, id, launcher, {ignoreRun}) {
   console.log('Measuring site:', url, 'run:', id);
   const parsedURL = parseURL(url);
   const urlBasedFilename = sanitizeURL(`${parsedURL.host}-${parsedURL.pathname}`);
@@ -182,20 +183,27 @@ function singleRunAnalysis(url, id, {ignoreRun}) {
   }
   const outputPath = path.resolve(runPath, constants.LIGHTHOUSE_RESULTS_FILENAME);
   const assetsPath = path.resolve(runPath, 'assets');
-  return analyzeWithLighthouse(url, outputPath, assetsPath, {ignoreRun});
+  return analyzeWithLighthouse(launcher, url, outputPath, assetsPath, {ignoreRun});
 }
 
 /**
  * Runs lighthouse and save the artifacts (not used directly by plots,
  * but may be helpful for debugging outlier runs).
+ * @param {!Launcher} launcher
  * @param {string} url
  * @param {string} outputPath
  * @param {string} assetsPath
  * @param {{ignoreRun: boolean}} options
  * @return {!Promise}
  */
-function analyzeWithLighthouse(url, outputPath, assetsPath, {ignoreRun}) {
-  const flags = {output: 'json'};
+function analyzeWithLighthouse(launcher, url, outputPath, assetsPath, {ignoreRun}) {
+  const flags = {
+    output: 'json',
+    disableCpuThrottling: ignoreRun ? true : args['disable-cpu-throttling'],
+    disableNetworkThrottling: ignoreRun ? true : args['disable-network-throttling'],
+    disableDeviceEmulation: args['disable-device-emulation'],
+    port: launcher.port,
+  };
   return lighthouse(url, flags, config)
     .then(lighthouseResults => {
       if (ignoreRun) {