Benchmark: EventListener cost

Script Preparation code:

var audio = document.createElement("audio");

function andAOne(e){ 
  e.count = (e.count|| 0) +1; 
  e.count === 501 && e.preventDefault();
}

function andAOneAndAStop(e){ 
  e.count = (e.count|| 0) +1; 
  e.count === 501 && e.stopPropagationImmediately();
}

function andAOneAndANeverStop(e){ 
  e.count = (e.count|| 0) +1; 
  e.count === 5001 && e.stopPropagationImmediately();
}

Tests:

async 1000
for (var i = 0; i <100; i++) audio.addEventListener("ratechange",andAOne.bind({})); audio.playbackRate = 2;
async 501
for (var i = 0; i <100; i++) audio.addEventListener("ratechange",andAOneAndAStop.bind({})); audio.playbackRate = 2;
sync 1000
for (var i = 0; i <100; i++) audio.addEventListener("click",andAOne.bind({})); audio.click();
sync 501
for (var i = 0; i <100; i++) audio.addEventListener("click",andAOneAndAStop.bind({})); audio.click();
sync 1000 with a fake stopImmediatePropagation()
for (var i = 0; i <100; i++) audio.addEventListener("click",andAOneAndANeverStop.bind({})); audio.click();
async 1000 with a fake stopImmediatePropagation()
for (var i = 0; i <100; i++) audio.addEventListener("ratechange",andAOneAndANeverStop.bind({})); audio.playbackRate = 2;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
async 1000
async 501
sync 1000
sync 501
sync 1000 with a fake stopImmediatePropagation()
async 1000 with a fake stopImmediatePropagation()

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:79.0) Gecko/20100101 Firefox/79.0

Browser/OS: Firefox 79 on Linux

View result in a separate tab

Test name	Executions per second
async 1000	10.3 Ops/sec
async 501	4.0 Ops/sec
sync 1000	24.7 Ops/sec
sync 501	8.4 Ops/sec
sync 1000 with a fake stopImmediatePropagation()	6.3 Ops/sec
async 1000 with a fake stopImmediatePropagation()	3.7 Ops/sec

EventListener cost (version: 2)

what are the costs of running different event listeners?

Comparing performance of: async 1000 vs async 501 vs sync 1000 vs sync 501 vs sync 1000 with a fake stopImmediatePropagation() vs async 1000 with a fake stopImmediatePropagation()

Created: 3 years ago by: Registered User

Jump to the latest result

async 1000

async 501

sync 1000

sync 501

sync 1000 with a fake stopImmediatePropagation()

async 1000 with a fake stopImmediatePropagation()

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A