将 process.hrtime() 转换为毫秒

问题描述

我有使用 hrtime

的现有代码

before = process.hrtime()

// stuff happens...

after = process.hrtime(before)

latency = (after[0] * 1000000000 + after[1]) / 1000000;

上面的latency是什么单位？

解决方法

事实证明上面的实际上是毫秒。由于 setTimeout 以毫秒为单位获取延迟值，因此很容易验证我的 hrtime 杂耍：

const times = []
const delays = [1,10,100,1000,1001,1100];

function sleep(ms) {
    return new Promise((res) => {
        setTimeout(res,ms);
    });
}

async function main() {
    for (let ms of delays) {
        const ping = process.hrtime();
        await sleep(ms);
        const pong = process.hrtime(ping);
        const latency = (pong[0] * 1000000000 + pong[1]) / 1000000;
        times.push(latency);
    }

    console.log(times);
    // >>> [2.031091,11.623596,101.971041,1000.554953,1001.192077,1104.29338]
}

main();