Benchmark: Custom Event vs PubSub Single Event

Tests:

Custom Event
let i = 1001; const results = []; while (--i) { window.dispatchEvent(new CustomEvent('custom:test')); }
PubSub
class PubSub { constructor() { this.events = {}; } subscribe(event, callback) { if (!this.events.hasOwnProperty(event)) { this.events[event] = []; } return this.events[event].push(callback); } publish(event, data = {}) { if (!this.events.hasOwnProperty(event)) { return []; } return this.events[event].map((callback) => callback(data)); } } const pubSub = new PubSub(); let i = 1001; const results = []; while (--i) { pubSub.publish('custom', 'test') }

Rendered benchmark preparation results:

Previous results

Test case name	Result
Custom Event
PubSub

ⓘ Get performance results from real users on your website with Request Metrics.

Latest run results:

Run details: (Test run date: 16 days ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:125.0) Gecko/20100101 Firefox/125.0

Browser/OS: Firefox 125 on Mac OS X 10.15

Test name	Executions per second
Custom Event	1104.9 Ops/sec
PubSub	85442.9 Ops/sec

Custom Event vs PubSub Single Event (version: 0)