Webpack Stress Test

gen.js

const fs = require('fs');
const path = require('path');
const { randomBytes } = require('crypto');

function randomString(size) {
  return randomBytes(size).toString('hex');
}

function randomInt(min, max) {
  return Math.floor(Math.random() * (max - min + 1) + min);
}

const dir = path.resolve(__dirname, `./src/modules/`);
if (!fs.existsSync(dir)) {
  fs.mkdirSync(dir, { recursive: true });
}

const lazyImports = [];
const lazyChunks = 100;
const totalChunks = 10_000;

for (let i = 0; i <= totalChunks; i++) {
  const filePath = path.resolve(dir, `${i}.js`);
  fs.writeFileSync(filePath, `export default "${randomString(randomInt(1000, 20_000))}";\n`);
  lazyImports.push(`import('modules/${i}').then(console.log);`);
  if (i % lazyChunks === 0) {
    fs.appendFileSync(filePath, lazyImports.slice(-lazyChunks, -1).join('\n'));
  }
}

for (let i = 0; i < 5; i++) {
  const indexFilePath = path.resolve(__dirname, `./src/index_${i}.js`);
  fs.writeFileSync(indexFilePath, lazyImports.filter((_, i) => i % lazyChunks === 0).join('\n'));
}

package.json

{
  "devDependencies": {
    "webpack": "5.76.0",
    "webpack-cli": "5.0.1"
  },
  "scripts": {
    "gen": "node gen.js",
    "start": "webpack build --mode=production --progress=profile"
  }
}

webpack.config.js

const path = require('path');

module.exports = {
  entry: Object.fromEntries(Array.from({ length: 5 }, (_, i) => [`index_${i}`, `./src/index_${i}.js`])),
  output: {
    filename: '[name]-[contenthash].js',
    chunkFilename: `[name]-[contenthash].js`,
    path: path.resolve(__dirname, 'dist'),
  },
  resolve: {
    modules: [path.resolve(__dirname, 'src')]
  },
  optimization: {
    realContentHash: true,
    splitChunks: {
      chunks: 'all',
    },
  },
};