Check how long an operation takes | Javascript
//The performance.now() method returns a DOMHighResTimeStamp, measured in milliseconds.
//performance.now() is relative to page load and more precise in orders of magnitude.
//Use cases include benchmarking and other cases where a high-resolution time is required
//such as media (gaming, audio, video, //etc.)
var startTime = performance.now();
doSomething();
const endTime = performance.now();
console.log("this doSomething took " + (endTime - startTime) + " milliseconds.");
This code snippet measures the time it takes to execute the `doSomething()` function using the `performance.now()` method. Here's how it works: 1. `var startTime = performance.now();`: This line stores the timestamp in milliseconds when this line is executed in the `startTime` variable. This marks the starting point for measuring the duration of code execution. 2. `doSomething();`: This line calls the `doSomething()` function, which is presumably a function that takes an unknown amount of time to complete its tasks. 3. `const endTime = performance.now();`: This line captures the timestamp in milliseconds after the `doSomething()` function has finished executing in the `endTime` constant. This marks the ending point for measuring the duration of code execution. 4. `console.log("this doSomething took " + (endTime - startTime) + " milliseconds.");`: This line calculates the duration by subtracting the `startTime` from the `endTime` and logs the result to the console. It tells us how many milliseconds it took to execute the `doSomething()` function. This code is useful for measuring the performance of a specific function or a block of code and is commonly used for benchmarking purposes to optimize code and identify potential performance bottlenecks.