Benchmark: Symbol vs Object identity access speed

Symbol vs Object identity access speed (version: 0)

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

Comparing performance of: `Symbol read: Object vs Symbol read: Set vs Symbol read: Map vs Object read: Set vs Object read: Map vs Symbol write: Object vs Symbol write: Set vs Symbol write: Map vs Object write: Set vs Object write: Map vs Symbol insert: Object vs Symbol insert: Set vs Symbol insert: Map vs Object insert: Set vs Object insert: Map`

Created: 2 years ago by: Registered User

Go to the latest result

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);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
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

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:123.0) Gecko/20100101 Firefox/123.0

Browser/OS: Firefox 123 on Windows

View result in a separate tab

Symbol read: Set

143K/s

Symbol read: Map

134K/s

Object read: Set

97K/s

Object read: Map

96K/s

Symbol read: Object

74K/s

Symbol write: Object

69K/s

Symbol insert: Set

65K/s

Symbol write: Set

65K/s

Symbol insert: Map

56K/s

Symbol insert: Object

55K/s

Symbol write: Map

53K/s

Object insert: Set