How can I get the most accurate time stamp in Node.js?
ps My version of Node.js is 0.8.X and the node-microtime extension doesn\'t work for me (crash on install)
To work with more precision than Date.now()
, but with milliseconds in float precision:
function getTimeMSFloat() {
var hrtime = process.hrtime();
return ( hrtime[0] * 1000000 + hrtime[1] / 1000 ) / 1000;
}
new Date().getTime()
? This gives you a timestamp in milliseconds, which is the most accurate that JS will give you.
Update: As stated by vaughan, process.hrtime()
is available within Node.js - its resolution are nanoseconds and therefore its much higher, also this doesn't mean it has to be more exact.
PS.: Just to be clearer, process.hrtime()
returns you a tuple Array
containing the current high-resolution real time in a [seconds, nanoseconds]
A rewrite to help quick understanding:
const hrtime = process.hrtime(); // [0] is seconds, [1] is nanoseconds
let nanoSeconds = (hrtime[0] * 1e9) + hrtime[1]; // 1 second is 1e9 nano seconds
console.log('nanoSeconds: ' + nanoSeconds);
//nanoSeconds: 97760957504895
let microSeconds = parseInt(((hrtime[0] * 1e6) + (hrtime[1]) * 1e-3));
console.log('microSeconds: ' + microSeconds);
//microSeconds: 97760957504
let milliSeconds = parseInt(((hrtime[0] * 1e3) + (hrtime[1]) * 1e-6));
console.log('milliSeconds: ' + milliSeconds);
//milliSeconds: 97760957
Source: https://nodejs.org/api/process.html#process_process_hrtime_time
Get hrtime
as single number in one line:
const begin = process.hrtime();
// ... Do the thing you want to measure
const nanoSeconds = process.hrtime(begin).reduce((sec, nano) => sec * 1e9 + nano)
Array.reduce
, when given a single argument, will use the array's first element as the initial accumulator
value. One could use 0
as the initial value and this would work as well, but why do the extra * 0
.
I'm not so proud about this solution but you can have timestamp in microsecond or nanosecond in this way:
const microsecond = () => Number(Date.now() + String(process.hrtime()[1]).slice(3,6))
const nanosecond = () => Number(Date.now() + String(process.hrtime()[1]).slice(3))
// usage
microsecond() // return 1586878008997591
nanosecond() // return 1586878009000645600
// Benchmark with 100 000 iterations
// Date.now: 7.758ms
// microsecond: 33.382ms
// nanosecond: 31.252ms
Know that:
Date.now()
Date.now()
by Number(new Date())
to get timestamp in millisecondsEdit:
Here a solution to have microsecond with comma, however, the number version will be rounded natively by javascript. So if you want the same format every time, you should use the String version of it.
const microsecondWithCommaString = () => (Date.now() + '.' + String(process.hrtime()[1]).slice(3,7))
const microsecondWithComma = () => Number(Date.now() + '.' + String(process.hrtime()[1]).slice(3,7))
microsecondWithCommaString() // return "1586883629984.8997"
microsecondWithComma() // return 1586883629985.966
Node.js nanotimer
I wrote a wrapper library/object for node.js on top of the process.hrtime
function call. It has useful functions, like timing synchronous and asynchronous tasks, specified in seconds, milliseconds, micro, or even nano, and follows the syntax of the built in javascript timer so as to be familiar.
Timer objects are also discrete, so you can have as many as you'd like, each with their own setTimeout
or setInterval
process running.
It's called nanotimer. Check it out!