Run results for: Immutable vs Native

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/75.0.3770.142 Safari/537.36

Browser: Chrome 75

Operating system: Mac OS X 10.14.6

Device Platform: Desktop

Date tested: 5 years ago

Test name	Executions per second
native copy	17.5 Ops/sec
immutable copy	216033.0 Ops/sec

HTML Preparation code:

<script src="https://cdnjs.cloudflare.com/ajax/libs/immutable/3.8.1/immutable.min.js"></script>

Script Preparation code:

var native = [];
for (var i=0; i < 1000000; i++) {
  native.push(i);
}
var imm = Immutable.List(native);

Tests: