Run results for: Copy map vs. object 10000

Run details:

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0.0.0 Mobile Safari/537.36

Browser: Chrome Mobile 130

Operating system: Android

Device Platform: Mobile

Date tested: one year ago

Test name	Executions per second
Copy obj	465.1 Ops/sec
Copy map	1771.6 Ops/sec

Script Preparation code:

var items = Array.from({
    length: 10000
}, (_, i) => ({
    id: `item-${i}`
}))

var dataObj = {};

items.forEach((item, i) => {
  dataObj[item.id] = {
    start: i * 30,
    end: i * 30 + 30
  }
});

var dataMap = new Map();

items.forEach((item, i) => {
  dataMap.set(item.id, {
    start: i * 30,
    end: i * 30 + 30
  });
});

Tests:

Copy obj
const obj = { ...dataObj };
Copy map
const map = new Map(dataMap);

Run results for: Copy map vs. object 10000

Copy obj

Copy map