README.md

⏱️ perfTime

PerfTime is a simple and flexible utility for measuring function execution time. No depenencies.

It works by wrapping the performance.now() method and gives you a simple to use API for quick debugging purposes

Installation:

npm i @tzwel/perftime

Then require it in your project

const perfTime = require('@tzwel/perftime')

Usage:

One-liner

You can pass your function to perfTime and then call the .run() method. This exectues the function, measures its execution time and then logs the result.

new perfTime({function: yourFunctionHere}).run()
new perfTime({function: asyncFunction}).runAsync() // for asynchronous functions

Basic usage

function someRandomFunction() {
	// initialize perfTime and start measuring
	const measurement = new perfTime('function name (or you can leave this blank)').start()

	// code to be measured goes here

	measurement.stop() // stop the measurement and log results
	// => Executing 'someRandomFunction' took 0.006400000000000735ms
}

You can also start the measurement at any point later:

const measurement = new perfTime({function: someRandomFunction})
measurement.start()
// code to be measured goes here
measurement.stop()

The name of the measured function can be set in four different ways;

PerfTime accepts an options object or a string with a name as argument

new perfTime('some function name') // string name
new perfTime({functionName: 'some function name'}) // options object with provided function name
new perfTime({function: someFunction}) // options object with the function name derived automatically from the passed function
new perfTime() // empty, function gets called an *unnamed function*

Multiple measures and average

You can measure a function multiple times and then get its average execution time

Warning

When getting average time, the first result always gets omitted because the first function call is always slower before optimizations take place

It can be done using the one-liner like this:

const measurement = new perfTime({function: someRandomFunction}).run(5) // benchmarks the function 5 times
console.log(measurement.averageTime) // log the average time of execution

// Async variant:
new perfTime({function: asyncFunction}).runAsync(5).then((measurement)=> {
	console.log(measurement.averageTime);
})

Or inside the function like this:

function someRandomFunction() {
	const measurement = new perfTime({function: someRandomFunction})
	
	for (let index = 0; index < 15; index++) { // a for loop that executes code multiple times
		measurement.start()
		// function code to be measured goes here
		measurement.stop()
	}

	console.log(measurement.averageTime);
}

Or by wrapping the function call in a for loop (you can implement this however you want)

const measurement = new perfTime({function: someRandomFunction})
for (let index = 0; index < 15; index++) {
	measurement.start()
	someRandomFunction()
	measurement.stop()
}
console.log(measurement.averageTime);

Async

Currently async functions can only be benchmarked using runAsync and are run one by one, not in parallel