Run results for: Array constructor vs literal performance

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/53.0.2785.116 Safari/537.36

Browser: Chrome 53

Operating system: Mac OS X 10.12.0

Device Platform: Other

Date tested: 7 years ago

Test name	Executions per second
Array constructor - 10 items	4245485.0 Ops/sec
Array literal - 10 items	17309080.0 Ops/sec
Array literal (assign by index) - 10 items	18234640.0 Ops/sec
Array literal (explicit length) - 10 items	7530504.0 Ops/sec
Array constructor - 1000 items	197481.6 Ops/sec
Array literal - 1000 items	198472.6 Ops/sec
Array literal (assign by index) - 1000 items	210236.6 Ops/sec
Array literal (explicit length) - 1000 items	437439.2 Ops/sec
Array constructor - 100000 items	1015.6 Ops/sec
Array literal - 100000 items	915.9 Ops/sec
Array literal (assign by index) - 100000 items	947.2 Ops/sec
Array literal (explicit length) - 100000 items	1474.1 Ops/sec

Tests:

Array constructor - 10 items
var n = 10; var arr = new Array(n); for (var i = 0; i < n; i++) { arr[i] = i; }
Array literal - 10 items
var n = 10; var arr = []; for (var i = 0; i < n; i++) { arr.push(i); }
Array literal (assign by index) - 10 items
var n = 10; var arr = []; for (var i = 0; i < n; i++) { arr[i] = i; }
Array literal (explicit length) - 10 items
var n = 10; var arr = []; arr.length = n; for (var i = 0; i < n; i++) { arr[i] = i; }
Array constructor - 1000 items
var n = 1000; var arr = new Array(n); for (var i = 0; i < n; i++) { arr[i] = i; }
Array literal - 1000 items
var n = 1000; var arr = []; for (var i = 0; i < n; i++) { arr.push(i); }
Array literal (assign by index) - 1000 items
var n = 1000; var arr = []; for (var i = 0; i < n; i++) { arr[i] = i; }
Array literal (explicit length) - 1000 items
var n = 1000; var arr = []; arr.length = n; for (var i = 0; i < n; i++) { arr[i] = i; }
Array constructor - 100000 items
var n = 100000; var arr = new Array(n); for (var i = 0; i < n; i++) { arr[i] = i; }
Array literal - 100000 items
var n = 100000; var arr = []; for (var i = 0; i < n; i++) { arr.push(i); }
Array literal (assign by index) - 100000 items
var n = 100000; var arr = []; for (var i = 0; i < n; i++) { arr[i] = i; }
Array literal (explicit length) - 100000 items
var n = 100000; var arr = []; arr.length = n; for (var i = 0; i < n; i++) { arr[i] = i; }