Run results for: Symbol vs Object identity access speed

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.0.0 Safari/537.36

Browser: Chrome 122

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
Symbol read: Object	211578.3 Ops/sec
Symbol read: Set	128679.9 Ops/sec
Symbol read: Map	126022.5 Ops/sec
Object read: Set	293975.9 Ops/sec
Object read: Map	208615.2 Ops/sec
Symbol write: Object	198248.0 Ops/sec
Symbol write: Set	121810.6 Ops/sec
Symbol write: Map	87429.0 Ops/sec
Object write: Set	213914.0 Ops/sec
Object write: Map	159648.5 Ops/sec
Symbol insert: Object	197097.5 Ops/sec
Symbol insert: Set	119531.1 Ops/sec
Symbol insert: Map	88007.0 Ops/sec
Object insert: Set	222465.2 Ops/sec
Object insert: Map	168228.2 Ops/sec

Script Preparation code:

var objects = [];
var symbols = [];
var symbolObj = {__proto__: null};
var symbolMap = new Map();
var symbolSet = new Set();
var objectMap = new Map();
var objectSet = new Set();
var emptyObj = {__proto__: null};
var emptyMap = new Map();
var emptySet = new Set();

for (let i = 0; i < 1000; i++) {
  objects[i] = {i, sym: Symbol(i)};
  symbols[i] = objects[i].sym;
  symbolObj[symbols[i]] = i;
  symbolSet.add(symbols[i]);
  symbolMap.set(symbols[i], i);
  objectSet.add(objects[i]);
  objectMap.set(objects[i], i);
}

function objRead(obj, keys) {
  let total = 0;
  for (const key of keys) {
    total += obj[key];
  }
  return total;
}
function objWrite(obj, keys) {
  for (const key of keys) {
    obj[key] = true;
  }
}
function mapRead(map, keys) {
  let total = 0;
  for (const key of keys) {
    total += map.get(key);
  }
  return total;
}
function mapWrite(map, keys) {
  for (const key of keys) {
    map.set(key, true);
  }
}
function setRead(set, keys) {
  let total = 0;
  for (const key of keys) {
    total += set.has(key) ? 1 : 0;
  }
  return total;
}
function setWrite(set, keys) {
  for (const key of keys) {
    set.add(key);
  }
}

Tests:

Symbol read: Object
objRead(symbolObj, symbols)
Symbol read: Set
setRead(symbolSet, symbols)
Symbol read: Map
mapRead(symbolMap, symbols)
Object read: Set
setRead(objectSet, objects)
Object read: Map
mapRead(objectMap, objects)
Symbol write: Object
objWrite(symbolObj, symbols)
Symbol write: Set
setWrite(symbolSet, symbols)
Symbol write: Map
mapWrite(symbolMap, symbols);
Object write: Set
setWrite(objectSet, objects);
Object write: Map
mapWrite(objectMap, objects);
Symbol insert: Object
objWrite(emptyObj, symbols);
Symbol insert: Set
setWrite(emptySet, symbols);
Symbol insert: Map
mapWrite(emptyMap, symbols);
Object insert: Set
setWrite(emptySet, objects);
Object insert: Map
mapWrite(emptyMap, objects);

Run results for: Symbol vs Object identity access speed

Testing JS Map/Set/Object lookup speed of unregistered Symbols vs Object identity

Symbol read: Object

Symbol read: Set

Symbol read: Map

Object read: Set

Object read: Map

Symbol write: Object

Symbol write: Set

Symbol write: Map

Object write: Set

Object write: Map

Symbol insert: Object

Symbol insert: Set

Symbol insert: Map

Object insert: Set

Object insert: Map