Node.js Cluster usage with simple worker delegation

multiplier.js

const cluster = require('cluster');

const MULTIPLY_EVENT = 'multiply';

if (cluster.isMaster) {
  (function run({ dataset, compare, length }) {
    if (global.gc) global.gc();

    const results = [];

    const workers = [];

    for (let i = 0; i < require('os').cpus().length; i += 1) {
      const worker = cluster.fork();

      workers.push(worker);

      worker.on('message', data => {
        results.push(data.result);
        workers.push(worker);
      });
    }

    // instead of a while loop, which shuts down the event loop.
    setInterval(() => {
      if (length === results.length) {
        // all our work is done.
        const total = results.reduce((value, next) => value + next, 0);

        console.log(`total: ${total}, comparison: ${compare}`);

        process.exit();
      } else {
        const worker = workers.shift();

        // check if worker is available
        if (worker) {
          const set = dataset.pop();

          // data remains
          if (set) worker.send({ type: MULTIPLY_EVENT, set });
        }
      }
    }, 0);
  })(
    (function generateDataset(iterations) {
      let dataset;

      if (iterations && typeof iterations === 'number') {
        const magnitude = 100;
        const gen = () => Math.trunc(Math.random() * magnitude);

        dataset = Array(iterations)
          .fill('', -1 * iterations)
          .map(() => [gen(), gen()]);
      } else dataset = [[99, 2], [11, 2], [3, 3], [8, 9], [11, 4]];

      const compare = dataset.reduce((value, next) => {
        const [a, b] = next;

        return value + a * b;
      }, 1);

      return { dataset, compare, length: dataset.length };
    })(12 /* number of iterations */),
  );
} else {
  process.on('message', data => {
    switch (data.type) {
      default:
        break;
      case MULTIPLY_EVENT:
        process.send({
          result: data.set.reduce((value, next) => value * next, 1),
        });
        break;
    }
  });
}