(async () => {
  const { job, start, stop } = require("microjob");

  try {
    // start the worker pool
    console.time("microjob");
    await start();

    // this function will be executed in another thread
    const res = await job(() => {
      let i = 0;
      const result = [];
      const threadCount = 4;
      const totalDataLength = 2000000;
      for (i = 0; i < threadCount; i++) {
        // heavy CPU load ...
        const crypto = require("crypto");
        const sha256 = (s) => crypto.createHash("sha256").update(s).digest();
        const shaArray = Array.from(Array(totalDataLength / threadCount)).map((num) =>
          sha256(String(num))
        );
        result.push(shaArray);
      }
      return result;
    });

    console.log(res);
    console.timeEnd("microjob");
  } catch (err) {
    console.error(err);
  } finally {
    // shutdown worker pool
    await stop();
  }
})();

const { Worker } = require("worker_threads");
const path = require("path");
console.time('thread')
let workerPool = [];
const threadCount = 4;
const totalDataLength = 2000000;
for (let i = 0; i < threadCount; i++) {
  const workerInstance = new Promise((resolve, reject) => {
    const worker = new Worker(path.resolve("./worker.js"));
    worker.on("message", ({ data }) => {
      resolve(data);
    });
    worker.postMessage({
      arrayLength: totalDataLength / threadCount,
    });
  });
  workerPool.push(workerInstance);
}
Promise.all(workerPool)
  .then((values) => {
    console.log(values);
    console.timeEnd('thread')
  })
  .catch((err) => {
    console.log(err);
  });

const { parentPort } = require("worker_threads");
const crypto = require("crypto");
const sha256 = (s) => crypto.createHash("sha256").update(s).digest();

parentPort.on("message", ({ arrayLength }) => {
  const shaArray = Array.from(Array(arrayLength)).map((num) => sha256(String(num)));
  parentPort.postMessage({
    data: shaArray,
  });
});