es6 map vs array vs obj performance test

map-perf.js

"use strict";

let looper = (callback) => {
  let n = 2000000;
  while (n > 0) {
    callback(n);
    n--;
  }
};

let timer = (log, callback) => {
  let start = Date.now();
  callback();
  console.log(log, Date.now() - start);
};

let map = new Map();
let obj = {};
let ray = [];

for (let i = 0; i < 2000000; i++) {
  ray.push(i);
}

function RandomIndex(count) {
  return Math.floor(Math.random() * count);
}

timer("Map int key set took: ", () =>
  looper((index) => map.set(RandomIndex(2000000), index))
);
timer("Obj int key set took: ", () =>
  looper((index) => (obj[RandomIndex(2000000)] = index))
);
timer("ray int key set took: ", () =>
  looper((index) => (ray[RandomIndex(2000000)] = index))
);
console.log();
timer("Map int key get took: ", () =>
  looper((index) => {
    let dummylet = map.get(RandomIndex(2000000));
  })
);
timer("Obj int key get took: ", () =>
  looper((index) => {
    let dummylet = obj[RandomIndex(2000000)];
  })
);
timer("ray int key get took: ", () =>
  looper((index) => {
    let dummylet = ray[RandomIndex(2000000)];
  })
);
console.log();
timer("Map int key iter took: ", () =>
  Array.from(map).forEach(([key, val]) => {
    let dummylet = val;
  })
);
timer("Obj int key iter took: ", () =>
  Object.entries(obj).forEach(([key, val]) => {
    let dummylet = val;
  })
);
timer("Ray int key iter took: ", () =>
  ray.forEach((val, key) => {
    let dummylet = val;
  })
);

console.log("\n\n");

map = new Map();
obj = {};
ray = [];

timer("Map string key set took: ", () =>
  looper((index) => map.set("" + RandomIndex(2000000), "" + index))
);
timer("Obj string key set took: ", () =>
  looper((index) => (obj["" + RandomIndex(2000000)] = "" + index))
);
timer("ray string key set took: ", () =>
  looper((index) => (ray["" + RandomIndex(2000000)] = "" + index))
);
console.log();
timer("Map string key get took: ", () =>
  looper((index) => {
    let dummylet = map.get("" + RandomIndex(2000000));
  })
);
timer("Obj string key get took: ", () =>
  looper((index) => {
    let dummylet = obj["" + RandomIndex(2000000)];
  })
);
timer("ray string key get took: ", () =>
  looper((index) => {
    let dummylet = ray["" + RandomIndex(2000000)];
  })
);
console.log();
timer("Map string key iter took: ", () =>
  Array.from(map).forEach(([key, val]) => {
    let dummylet = val;
  })
);
timer("Obj string key iter took: ", () =>
  Object.entries(obj).forEach(([key, val]) => {
    let dummylet = val;
  })
);
timer("Ray string key iter took: ", () =>
  ray.forEach((val, key) => {
    let dummylet = val;
  })
);

// node --version: v18.11.0

// Map int key set took:  210
// Obj int key set took:  148
// ray int key set took:  25

// Map int key get took:  23
// Obj int key get took:  22
// ray int key get took:  21

// Map int key iter took:  87
// Obj int key iter took:  292
// Ray int key iter took:  10



// Map string key set took:  820
// Obj string key set took:  463
// ray string key set took:  448

// Map string key get took:  35
// Obj string key get took:  84
// ray string key get took:  84

// Map string key iter took:  93
// Obj string key iter took:  521
// Ray string key iter took:  16