Process hrtime. The process object is an instance of EventEmitter.

Process hrtime To get current time in microseconds, do the following: The meaning of these values is defined in the documentation (although it's easy to miss, since it's just one line): These times are relative to an arbitrary time in the past, and not related to the time of day and therefore not subject to clock drift. hrtime () give time in [seconds, nanoseconds] while process. And this is not just some misreporting, but rather actual behaviour - if look at the remote http server logs, i see that all requests actually took time reported by hrtime, and time reported by getTime () is actually how long the node. log(result); }); process. hrtime() and then later let timestamp = process. hrtime(); for (let i = 0; i < 9999999999; i++) { //Heavy Calculation or API Hit } let stop = process. 8, last published: 4 years ago. bigint ()` to seconds, milliseconds, nanoseconds. let start = process. browser support for process. Aug 22, 2025 · 関数の概要 process. Jun 29, 2016 · So sometimes the difference between hrtime and getTime () is huge. hrtime You may pass in the result of a previous call to process. hrtime() method returns the current high-resolution real time in a [seconds, nanoseconds] tuple Array, where nanoseconds is the remaining part of the real time that can't be represented in second precision. hrtime() UPDATE: The present package (available via npm install present) provides some sugar around hrtime if you'd like it. Jul 29, 2021 · The process. js worker threads can boost performance by offloading tasks to background threads—simple, efficient, and headache-free! ¥The process. Given you only care about seconds, Date. We used it to calculate the total time in the nanosecond between the process by subtracting the start time and end time. bigint to return the current timestamp in nanoseconds as a JavaScript bigint. now() (which provides milliseconds as an integer) is sufficient and a lot easier to work with. js empties its event loop and has no additional work to schedule. g. Works with timescales ranging from weeks to nanoseconds. js, this example focuses only to the timings: const timings = { // use process. hrtime function. It will use process. hrtime with start to return the timestamp of the elasped time and assign that to endTime. Convert the result of `process. Latest version: 5. hrtime and process. 0. bigint() issue, you might have to either add/update your @types/node type declarations dependency and/or Node itself In my own project, I've also used this code below for providing backward compatibility with older Node versions (though w/ obvious lack of precision): Jul 23, 2025 · console. In-depth documentation, guides, and reference materials for building secure, high-performance JavaScript and TypeScript applications with Deno Oct 7, 2016 · process. js, but provides a matching API and response format. The most comprehensive JavaScript process. bigint() to call process. bigint method. It can also be explicitly accessed using require (): May 18, 2017 · @bnoordhuis The first process. performance object with - among others - a now method which gives time in milliseconds, but with sub-millisecond precision. Jan 9, 2025 · In Node. Jan 15, 2021 · Turns out the above is in fact milliseconds. hrtime 1. The 'beforeExit' event is emitted when Node. Note: The browser environment does not support hrtime, so the best precision achievable in browsers is the microsecond level via performance. Since setTimeout takes the delay value in milliseconds, it's easy to validate my hrtime juggling: You may pass in the result of a previous call to process. now, and lastly Date. However, in answer to your question, you should look at process. hrtime () and process. js, we need to subscribe to a specific request, response and socket events. Here is a short code snippet how to do this in Node. Jul 1, 2021 · Note: If measuring in Node, process. hrtime(start) Use hrtime independent of environment (node or browser). hrtime() /* add the function to be timed here, between time and endTime */ const endTime = process. This method, available since the early days of Node. Syntax Feb 13, 2018 · The process. As for the actual hrtime. Contribute to cabinjs/browser-hrtime development by creating an account on GitHub. log(`Duration: ${duration}ms`); // Outputs: Duration: 2000. hrtime () call as a parameter in the second process. bigint() returns accuracy in nanoseconds. 1. log ("starting"); var start = process. usage Use hrtime independent of environment (node or browser). The process object provides information about, and control over, the current Node. I created simple example: console. 3 • Public • Published 7 years ago Readme Code Beta 1 Dependency 3 Dependents 4 Versions Mar 2, 2022 · For instance, we write process. now (subject to implementation differences across browsers). . To better understand how these newer APIs work, let's look at an example. hrtime first and fallback if not present. uptime() gives you the number of seconds the process has been running, which you could use to determine its start time. Start using browser-hrtime in your project by running `npm i browser-hrtime`. mkdir myapp Step 2: Navigate to the project directory Call hrtime when you want to start the stopwatch, and call it again when your operation is done. hrtime() is a classic Node. prototype. bigint() ? Yes! We can also use that if you care about the execution time in BigInt. hrtime(t0)[1]/1000000; inside the callback. hrtime code examples. bigint () :- process. js的世界里， process. hrtime () method with its syntax, parameter, and examples. hrtime(), calculating the ELU is more complex than a single subtraction. hrtime(time) const seconds = endTime[0] const nanosecondsConvertedToSeconds = endTime[1] / 1e9 const totalSeconds = seconds + nanosecondsConvertedToSeconds performance-now Implements a function similar to performance. May 10, 2020 · For details see the specification or MDN. The precision of the returned time is at the millisecond level (10^-3), which is insufficient for many use cases. time(), performance. hrtime(); or is it some unknown reason I couldn't even fathom? Easily format the time from node. js that is called hrtime to get high resolution timings. hrtime () function, which is used to measure code execution time, returns the current high-resolution real-time in [seconds, nanoseconds]. Feb 13, 2025 · In this article, we will discuss the Node. hrtime () is] relative to an arbitrary time in the past, and not related to the time of day and therefore not subject to clock drift. What is the Node. hrtime). hrtime ()用法及代码示例 测量代码执行时间的 process. Then, Subtract the former from the latter and you have the elapsed time. The Node. Start using convert-hrtime in your project by running `npm i convert-hrtime`. Nov 24, 2008 · Note, that in order by measure asynchronous functions execution time, you should insert var timeInMilliseconds = process. About Convert the result of `process. js provides the `hrtime` function, which stands for high - resolution time. That could be slower system call overhead, or actual errors in the timings. hrtime() as it's not a subject of clock drift startAt: process. js, another option for measuring performance is process. hrtime () 方法返回数组，其中包括当前的 high-resolution 实时 [秒，纳秒]。 我们通过提供第一个 process. This preference is based on considerations of precision and clock synchronization. hrtime method is specifically designed for measuring time intervals. Oct 18, 2025 · Node. hrtime() happens in Benchmark. Implements a function similar to performance. The process object is an instance of EventEmitter. How about process. now (based on process. js docs describe the functionality quite nicely and include a good code sample. See documentation at nodejs. hrtime() are commonly used functions to measure the execution time of commands. hrtime(); You may pass in the result of a previous call to process. hrtime. hrtime () 调用返回的时间作为第二个 process. bigint () which uses the kernel high res clock directly through a syscall, it’s the most accurate clock available to you in node core. hrtime does what you want). end(). This function is useful for measuring the elapsed time between two points in a Node. hrtime() (ref variable) call. js, we can use the process. If you call hrtime now, and then again ten Nov 10, 2017 · process. hrtimeは、Node. Please consider following this project's author, Jon Schlinkert, and consider starring the project to show your ️ and support. As a global, it is always available to Node. bigint(). bigint ()`. js, remains reliable and provides time measurements in nanoseconds. jsに組み込まれている関数であり、高精度の時間測定を行うために使用されます。主な目的は、パフォーマンスの計測や処理時間の測定です。通常のDateオブジェクトではミリ秒単位までしか測定でき This is a convenience option because, unlike process. Seemingly I can use process. hrtime() 调用 diff 与当前时间的结果。 Jul 30, 2014 · process. There are 104 other projects in the npm registry using convert-hrtime. Find guides, explainers and how to's for every popular function in JavaScript. The `process. 123ms console. The time difference between sequential hrtime. hrtime () function? The process. hrtime() to get a diff reading, useful for benchmarks and measuring intervals: var time = process. bigint functions that also don’t depend on the system clock and increase the accuracy to nanoseconds. const NS_PER_SEC = 1e9; const time = process. log(`Benchmark took ${diff[0] * NS_PER Dec 2, 2022 · Does it have to be time related? If it's time related you may get away with setting a reference point first let ref = process. Conclusion To get an accurate timestamp in Node. hrtime() is is for measuring performance between intervals (docs) but it can be also used for measuring uptime with nanosecond precision. Sep 18, 2017 · What I learned today is that there is also a function in Node. js native process. hrtime () is it measures time very accurately execution time which lasts less than a millisecond. bigint () doesn't accept any argument process. Feb 26, 2022 · to create the elaspedTime function tyat calls process. js programs, prioritize process. ELU is similar to CPU utilization, except that it only measures event loop statistics and not CPU usage. hrtime() returns an array [seconds, nanoseconds], which provides high-resolution timing. js process. hrtime() reveals no elapsed time? Date. hrtime () call. Why does it matter anyway? If you're just trying to measure client latency, you call hrtime twice, and absolute time doesn't matter. Basically, you just need to wrap the function you want to measure to calculate its execution time. hrtime(); // [ 1800216, 25 ] setTimeout(() => { const diff = process. Steps to Setup Project Step 1: Make a folder structure for the project. hrtime 就像外科医生的手术刀——当普通计时器给你的是一张模糊的X光片时，它能提供清晰的核磁共振影像。 下次当你需要诊断性能疑难杂症时，不妨让这把"时间手术刀"出鞘。 试着在项目中用hrtime分析一个函数性能吧！ Use process. bigInt () calls is around 3-30 times larger on Bun than on Node. Aug 26, 2013 · The variable will be in the closure scope of your onRequest handler function so it'll work just the way you expect it to (assuming process. The Advantage of process. epoll Node. Using process. Also, there are some difference between process. It provides timestamps in nanoseconds, making it ideal for measuring short-duration events. hrtime If you’re working in Node. hrtime (); console. js Process. js provides process. hrtime ()` to seconds, milliseconds, nanoseconds const time = process. hrtime () method returns the current high-resolution real time in a [seconds, nanoseconds] tuple Array, where nanoseconds is the remaining part of the real time that can't be represented in second precision. parse-d test array; or is it caused by process. Is it realistic that a function invocation followed by a little bit of code and then another function invocation could all happen in a duration such that process. js is process. Modern browsers have a window. time 是可选参数，它必须是先前 process. Jan 21, 2024 · In this example, we use process. hrtime () 调用中的参数来测量代码执行时间。 Simple usage example of `process. The process object is a global that provides information about, and control over, the current Node. Starting with Node. hrtime for this. Jan 29, 2025 · Although not part of the perf_hooks module, process. org This module does not provide the same level of time precision as node. Jul 4, 2024 · Measuring HTTP timings in Node. hrtime, followed by performance. Jan 9, 2025 · The process. The returned array contains two elements, the first being seconds and the second nanoseconds. Using perf hooks Imagine we have an asynchronous function called someAction, and we want to know how long it takes to run. log ("star The process. hrtime () is the legacy version of process. js method that returns the current high-resolution real time in nanoseconds as a BigInt. js, "high resolution time" is made available via process. js 10, a new version of this method was introduced based on BigInt: process. process. hrtime() to record the time at the start and end of an operation. hrtime(time); // [ 1, 552 ] console. If we run into a scenario wherein we want to start measuring JavaScript execution time for multiple functions, we can make use of the Performance API and Performance Observer. The endTime is in nanoseconds. hrtime(). browser-process-hrtime Browser shim for Node. It returns a array with first element the time in seconds, and second element the remaining nanoseconds. Dec 11, 2020 · A slightly more accurate approach is to use process. It represents the percentage of time the event loop has spent outside the event loop's event provider (e. js applications without using require (). bigint (). As per the documentation: [The time returned from process. js application responds. js application with high precision. hrtime means that the reported time will be monotonically Apr 2, 2018 · Primary use of process. js To measure HTTP timings in Node. bigint () method returns the current high-resolution real-time in nanoseconds as a bigint in NodeJS. use process. This covers the ways of measuring JavaScript execution time. hrtime(), but it still has limitations and needs to be manually set everywhere you end to use it. hrtime(); process. Latest version: 1. now. start() and the second one happens in Benchmark. 0, last published: 3 years ago. hrtime(); Jan 17, 2025 · Learn how Node. Aug 3, 2013 · I am triing to get execution time of async function. hrtime. js API for high-resolution timing. hrtime() in the browser. bigint ()` function is a Node. It offers a way to measure time intervals with a much higher precision compared to the standard `Date` object in JavaScript. Sep 18, 2017 · Is it caused by a difference between the generated test array vs JSON. In Node. Apr 3, 2023 · We measure the code execution time by providing the time returned by the first process. Note that it returns a nanosecond time stamp so you’ll probably want to divide by 1000000 to get in ms. This module offers the same function based on the Node. hrtime means that the reported time will be May 12, 2025 · 总结 在Node. now(), console. hrtime(ref) this way, the timestamp will be relative to the time and date by the first process. There are 8 other projects in the npm registry using browser-hrtime. now(), process. hrtime(), dnsLookupAt: undefined, tcpConnectionAt: undefined Learn JavaScript - Benchmarking your code - measuring execution time Learn JavaScript - Benchmarking your code - measuring execution time Oct 26, 2017 · Turns out the equivalent in Node. It does not support an additional time argument because the difference can be computed directly by subtraction of the two bigints variables. So in other words, hrtime is only useful for calculating the time relative to another point in time. hrtime provides a high-resolution timer. hrtime (). js Node.