可以使用包装器函数轻松地报告任何现有函数的执行时间。

包装器用于扩展现有函数，以便在现有函数执行之前和之后执行某些操作——这是一种组合逻辑的方便方法。

下面是一个使用withDurationReporting包装器的例子:

// without duration reporting
const doSomethingThatMayTakeAWhile = async (someArg: string, anotherArg: number) => { 
  /** your logic goes here */
}

// with duration reporting
const doSomethingThatMayTakeAWhileWithReporting = withDurationReporting(
  'doSomethingThatMayTakeAWhile', 
  doSomethingThatMayTakeAWhile
);

// note: you can define the function with duration reporting directly, too
const doSomethingThatMayTakeAWhile = withDurationReporting(
  'doSomethingThatMayTakeAWhile', 
  async (someArg: string, anotherArg: number) => { 
    /** your logic goes here */
  }
)

这是包装器本身:

import { hrtime } from 'process';

const roundToHundredths = (num: number) => Math.round(num * 100) / 100; // https://stackoverflow.com/a/14968691/3068233

/**
 * a wrapper which reports how long it took to execute a function, after the function completes
 */
export const withDurationReporting = <R extends any, T extends (...args: any[]) => Promise<R>>(
  title: string,
  logic: T,
  options: {
    reportingThresholdSeconds: number;
    logMethod: (message: string, metadata?: Record<string, any>) => void;
  } = {
    reportingThresholdSeconds: 1, // report on anything that takes more than 1 second, by default
    logMethod: console.log, // log with `console.log` by default
  }, 
) => {
  return (async (...args: Parameters<T>): Promise<R> => {
    const startTimeInNanoseconds = hrtime.bigint();
    const result = await logic(...args);
    const endTimeInNanoseconds = hrtime.bigint();
    const durationInNanoseconds = endTimeInNanoseconds - startTimeInNanoseconds;
    const durationInSeconds = roundToHundredths(Number(durationInNanoseconds) / 1e9); // https://stackoverflow.com/a/53970656/3068233
    if (durationInSeconds >= options.reportingThresholdSeconds)
      options.logMethod(`${title} took ${durationInSeconds} seconds to execute`, { title, durationInSeconds });
    return result;
  }) as T;
};

对于任何想要获得时间流逝值而不是控制台输出的人:

使用process.hrtime()作为@D。Deriso建议，以下是我更简单的方法:

function functionToBeMeasured() {
    var startTime = process.hrtime();
    // do some task...
    // ......
    var elapsedSeconds = parseHrtimeToSeconds(process.hrtime(startTime));
    console.log('It takes ' + elapsedSeconds + 'seconds');
}

function parseHrtimeToSeconds(hrtime) {
    var seconds = (hrtime[0] + (hrtime[1] / 1e9)).toFixed(3);
    return seconds;
}

var start = +new Date();
var counter = 0;
for(var i = 1; i < LIMIT; i++){
    ++counter;
    db.users.save({id : i, name : "MongoUser [" + i + "]"}, function(err, saved) {
          if( err || !saved ) console.log("Error");
          else console.log("Saved");
          if (--counter === 0) 
          {
              var end = +new Date();
              console.log("all users saved in " + (end-start) + " milliseconds");
          }
    });
}

有一种方法是专门为这个设计的。签出process.hrtime();．

我基本上把这个放在应用的顶部。

var start = process.hrtime();

var elapsed_time = function(note){
    var precision = 3; // 3 decimal places
    var elapsed = process.hrtime(start)[1] / 1000000; // divide by a million to get nano to milli
    console.log(process.hrtime(start)[0] + " s, " + elapsed.toFixed(precision) + " ms - " + note); // print message + time
    start = process.hrtime(); // reset the timer
}

然后我用它来看看函数需要多长时间。下面是一个基本的例子，打印一个名为"output.txt"的文本文件的内容:

var debug = true;
http.createServer(function(request, response) {

    if(debug) console.log("----------------------------------");
    if(debug) elapsed_time("recieved request");

    var send_html = function(err, contents) {
        if(debug) elapsed_time("start send_html()");
        response.writeHead(200, {'Content-Type': 'text/html' } );
        response.end(contents);
        if(debug) elapsed_time("end send_html()");
    }

    if(debug) elapsed_time("start readFile()");
    fs.readFile('output.txt', send_html);
    if(debug) elapsed_time("end readFile()");

}).listen(8080);

下面是一个可以在终端(BASH shell)中运行的快速测试:

for i in {1..100}; do echo $i; curl http://localhost:8080/; done

老问题，但一个简单的API和轻量级的解决方案;您可以使用perfy，它在内部使用高分辨率实时(process.hrtime)。

var perfy = require('perfy');

function end(label) {
    return function (err, saved) {
        console.log(err ? 'Error' : 'Saved'); 
        console.log( perfy.end(label).time ); // <——— result: seconds.milliseconds
    };
}

for (var i = 1; i < LIMIT; i++) {
    var label = 'db-save-' + i;
    perfy.start(label); // <——— start and mark time
    db.users.save({ id: i, name: 'MongoUser [' + i + ']' }, end(label));
}

注意，每次调用perfy.end(label)时，该实例都会被自动销毁。

披露:受D.Deriso的回答启发，编写了这个模块。文档。

调用console.time('label')将以毫秒为单位记录当前时间，然后调用console.timeEnd('label')将显示从该点开始的持续时间。

以毫秒为单位的时间会自动打印在标签旁边，所以你不需要单独调用console.log来打印标签:

console.time('test');
//some code
console.timeEnd('test'); //Prints something like that-> test: 11374.004ms

有关更多信息，请参阅console.time上的Mozilla开发者文档。