Benchmark: Various object iteration methods

Various object iteration methods (version: 1)

Comparing performance of: Object.keys w/ lookup, integer keys vs Object.values, integer keys vs Object.entries, integer keys vs for..in w/ lookup, integer keys vs for..in w/ lookup, integer keys, null proto vs Object.keys w/ lookup, string keys vs Object.values, string keys vs Object.entries, string keys vs for..in w/ lookup, string keys vs for..in w/ lookup, string keys, null proto

Created: 6 months ago by: Guest

Jump to the latest result

Script Preparation code:

const bigObject_int = Object.fromEntries(Array(1000).fill(null).map((_,i) => [i, i]));
const bigObject_int_NoProto = Object.assign({__proto__:null}, bigObject_int);
const bigObject_str = Object.fromEntries(Array(1000).fill(null).map((_,i) => [`_${i}`, i]));
const bigObject_str_NoProto = Object.assign({__proto__:null}, bigObject_str);

Tests:

Object.keys w/ lookup, integer keys
let x = 0; for (const key of Object.keys(bigObject_int)) { x += bigObject_int[key]; }
Object.values, integer keys
let x = 0; for (const i of Object.values(bigObject_int)) { x += i; }
Object.entries, integer keys
let x = 0; for (const [_, i] of Object.entries(bigObject_int)) { x += i; }
for..in w/ lookup, integer keys
let x = 0; for (const key in bigObject_int) { x += bigObject_int[key]; }
for..in w/ lookup, integer keys, null proto
let x = 0; for (const key in bigObject_int_NoProto) { x += bigObject_int_NoProto[key]; }
Object.keys w/ lookup, string keys
let x = 0; for (const key of Object.keys(bigObject_str)) { x += bigObject_str[key]; }
Object.values, string keys
let x = 0; for (const i of Object.values(bigObject_str)) { x += i; }
Object.entries, string keys
let x = 0; for (const [_, i] of Object.entries(bigObject_str)) { x += i; }
for..in w/ lookup, string keys
let x = 0; for (const key in bigObject_str) { x += bigObject_str[key]; }
for..in w/ lookup, string keys, null proto
let x = 0; for (const key in bigObject_str_NoProto) { x += bigObject_str_NoProto[key]; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object.keys w/ lookup, integer keys
Object.values, integer keys
Object.entries, integer keys
for..in w/ lookup, integer keys
for..in w/ lookup, integer keys, null proto
Object.keys w/ lookup, string keys
Object.values, string keys
Object.entries, string keys
for..in w/ lookup, string keys
for..in w/ lookup, string keys, null proto

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 6 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/141.0.0.0 Safari/537.36

Browser/OS: Chrome 141 on Windows

View result in a separate tab

Test name	Executions per second
Object.keys w/ lookup, integer keys	107050.5 Ops/sec
Object.values, integer keys	596619.1 Ops/sec
Object.entries, integer keys	43681.6 Ops/sec
for..in w/ lookup, integer keys	77454.4 Ops/sec
for..in w/ lookup, integer keys, null proto	77376.0 Ops/sec
Object.keys w/ lookup, string keys	23929.5 Ops/sec
Object.values, string keys	469029.4 Ops/sec
Object.entries, string keys	206169.1 Ops/sec
for..in w/ lookup, string keys	566013.3 Ops/sec
for..in w/ lookup, string keys, null proto	38031.9 Ops/sec

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