Run results for: Intl.DateTimeFormat new vs cached with lookup

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Browser: Chrome 114

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 10 months ago

Test name	Executions per second
new Intl.DateTimeFormat.format(date)	8817.6 Ops/sec
cached Intl.DateTimeFormat.format(date)	231447.5 Ops/sec
new Intl.DateTimeFormat.format(number)	8952.5 Ops/sec
cached Intl.DateTimeFormat.format(number)	245263.8 Ops/sec

Script Preparation code:

const TWO_DIGIT = '2-digit';

var options = {
      month: TWO_DIGIT,
      year: 'numeric',
      day: TWO_DIGIT,
      hour: TWO_DIGIT,
      hour12: false,
      minute: TWO_DIGIT,
      second: TWO_DIGIT,
    }

var cache = {
  [JSON.stringify(options)]: new Intl.DateTimeFormat('en-US', options)
};

var date = new Date();
var number = date.getTime();

Tests:

new Intl.DateTimeFormat.format(date)
new Intl.DateTimeFormat('en-US', options).format(date);
cached Intl.DateTimeFormat.format(date)
cache[JSON.stringify(options)].format(date);
new Intl.DateTimeFormat.format(number)
new Intl.DateTimeFormat('en-US', options).format(number);
cached Intl.DateTimeFormat.format(number)
cache[JSON.stringify(options)].format(number);

Run results for: Intl.DateTimeFormat new vs cached with lookup

measure the perf impact of caching calls to new Intl.DateTimeFormat

new Intl.DateTimeFormat.format(date)

cached Intl.DateTimeFormat.format(date)

new Intl.DateTimeFormat.format(number)

cached Intl.DateTimeFormat.format(number)