测量 web worker 的执行时间

Question

我想测量计算因式分解的网络工作者的执行时间。 webworker 正在向实时结果发送消息，一旦计算终止，webworker 就会发送 'finished' 消息。我在我的 React 应用程序中使用了 promise 来做到这一点。

useEffect(() => {
  const measureTimeStart = performance.now();
  (async () => {
    try {
      await new Promise(resolve => {
        const worker = new Worker(new URL('facto.js', import.meta.url));
        worker.postMessage(number);
        worker.onmessage = message => { //streaming live results 
          const { facto, status } = message.data;
          setResults({ ...facto }); //adding them to React state
          if (status === 'finished') {
            resolve();
            worker.terminate();
          };
        };
      });
    } catch (error) {
      console.log(error)
    }
  })();
  const measureTimeEnd = performance.now();
  setExecutionTime(Math.round((measureTimeEnd - measureTimeStart) * 1000) / 1000 + ' ms');
}, [number]); //number to factorize

但是，performance.now() 不会等待承诺解决，因此给了我任意时间。为什么？谢谢。

Answer 1

您需要等待 promise 解决后再测量时间。使用 finally 或 then

useEffect(() => {
  const measureTimeStart = performance.now();
  (async () => {
    try {
      await new Promise(resolve => {
        const worker = new Worker(new URL('facto.js', import.meta.url));
        worker.postMessage(number);
        worker.onmessage = message => { //streaming live results 
          const { facto, status } = message.data;
          setResults({ ...facto }); //adding them to React state
          if (status === 'finished') {
            resolve();
            worker.terminate();
          };
        };
      });
    } catch (error) {
      console.log(error)
    }
  })().finally(() => {
    const measureTimeEnd = performance.now();
    setExecutionTime(Math.round((measureTimeEnd - measureTimeStart) * 1000) / 1000 + ' ms');
  });
  
}, [number]); //number to factorize

Answer 2

useEffect(() => {
  runWebWorker()
}, [number])

async function runWebWorker() {
  const start = performance.now()
  await ...
  const end = performance.now()
}

或者，让您的工作人员发送性能数据，该数据更易于衡量并且不包括 postMessage 队列延迟。

测量 web worker 的执行时间

Measure execution time of web worker

javascript

reactjs

async-await

promise

web-worker