JSFiddle - React, Tailwind, and code Playground

JavaScript

const benchmarkMapMixed = size => {
	const start = performance.now();
  var map = new Map();
  for (var i = 0; i < size; i++) {
    map.set(i, i);
    var x = map.get(i);
    map.delete(i)
  }
  console.log('benchmarkMapMixed', performance.now() - start);
}

const benchmarkObjMixed = size => {
	const start = performance.now();
  var obj = {};
  for (var i = 0; i < size; i++) {
    obj[i] = i;
    var x = obj[i];
    delete obj[i];
  }
  console.log('benchmarkObjMixed', performance.now() - start);
}

const benchmarkMap = size => {
	const start = performance.now();
  var map = new Map();
  for (var i = 0; i < size; i++) map.set(i, i);
  for (var i = 0; i < size; i++) var x = map.get(i);
  for (var i = 0; i < size; i++) var x = map.delete(i);
  console.log('benchmarkMap', performance.now() - start);
}

const benchmarkObj = size => {
	const start = performance.now();
  var obj = {};
  for (var i = 0; i < size; i++) obj[i] = i;
  for (var i = 0; i < size; i++) var x = obj[i];
  for (var i = 0; i < size; i++) delete obj[i];
  console.log('benchmarkObj', performance.now() - start);
}

var size = 1000000;

benchmarkMap(size);
benchmarkObj(size);

benchmarkMapMixed(size);
benchmarkObjMixed(size);