Run results for: innerHTML vs replaceChildren() vs removeChild()|appendChild(cloneNode())

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:105.0) Gecko/20100101 Firefox/105.0

Browser: Firefox 105

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
innerHTML	3618259.2 Ops/sec
removechild & appendChild(cloneNode())	6058371.5 Ops/sec
replaceChildren	1821877.8 Ops/sec
Custom deleteChildren	6126553.5 Ops/sec
Custom replaceChildren via append	1657069.6 Ops/sec
Custom replaceChildren via appendChild	5998019.5 Ops/sec

HTML Preparation code:

<style id="CSS_Style">
  .expand-inline {
    display: block;
    padding: 0;
  }
  .expand-inline a {
    display: block;
    text-align: left;
  }
  .expand-inline a:hover {
    background-color: rgba(0, 105, 255, 0.05);
    text-decoration: none;
  }
  .pulsar-horizontal { display: inline-block; }
  .pulsar-horizontal>div {
    display: inline-block;
    width: 8px;
    height: 8px;
    padding: 2px;
    background-color: rgb(34, 136, 255);
    border-radius: 100%;
    animation-name: pulsing;
    animation-timing-function: ease-in-out;
    animation-iteration-count: infinite;
    animation-fill-mode: both;  
    animation-duration: 1s;
  }
  .pulsar-horizontal>div::nth-child(1) { animation-delay: 0s; }
  .pulsar-horizontal>div::nth-child(2) { animation-delay: 0.25s; }
  .pulsar-horizontal>div::nth-child(3) { animation-delay: 0.5s; }
  @keyframes pulsing {
    0%, 100%  {  transform: scale(0); opacity: 0.5; }
    50%       {  transform: scale(1); opacity: 1; }
  }
</style>
<template id='ELEMENTS'>
  <div class="pulsar-horizontal"><div></div><div></div><div></div></div> 
  <span class="expand-text">
    <a href="/r/IdiotsInCars/comments/vz8iju/other_driver_said_i_hit_him_technically_true_but/ig7o5tm/">continue this thread</a>
  </span>
  <a href="/r/IdiotsInCars/comments/vz8iju/other_driver_said_i_hit_him_technically_true_but/ig7o5tm/">continue this thread</a>
  <span class="deepthread expand-inline" data-comment-ids="ig7o5tm">
     <a href="/r/IdiotsInCars/comments/vz8iju/other_driver_said_i_hit_him_technically_true_but/ig7o5tm/">continue this thread</a>
     ::after
     <span class="gray">&nbsp;(3 replies)</span>
  </span> 
</template>

<div id="container">
</div>

Script Preparation code:

const template = document.getElementById('ELEMENTS').content;
var RESOURCES = {
  pulsar: 	  	template.children[0].cloneNode(true),
  pulsarStr: 	template.children[0].outerHTML,
  expand: 		template.children[1].cloneNode(true),
  expandStr:  	template.children[1].outerHTML,
  a: 			template.children[2].cloneNode(true),
  aStr:  		template.children[2].outerHTML, 
  deepthread: 	template.children[3].cloneNode(true), 
  container: 	document.getElementById('container'),
  get deepthreads() {
    return Array.from(this.container.childNodes);
  },
  deleteChildren(root) {
    while (root.firstChild) { root.lastChild.remove(); }
    return root;
  },  
  replaceChildren_append(root, ...replacements) {
    while (root.firstChild) { root.lastChild.remove(); }
    root.append(...replacements);
    return root;
  },  
  replaceChildren_appendChild(root, ...replacements) {
    while (root.firstChild) { root.lastChild.remove(); }
	for(let len=replacements.length, i=0; i<len; ++i) { root.appendChild(replacements[i]); }
    return root;
  }, 
};

for(let { container, deepthread }=RESOURCES, i = 0; i < 100; i++) {
  container.appendChild(deepthread.cloneNode(true));
}

Tests:

innerHTML
// caching vars doubles bench speed. The length of the scope chain to access values from preparation is excessive const { container, deepthreads, pulsarStr, expandStr } = RESOURCES; for(let len=deepthreads.length, i=0; i<len; ++i) { deepthreads[i].innerHTML = pulsarStr; } for(let len=deepthreads.length, i=0; i<len; ++i) { deepthreads[i].innerHTML = expandStr; } for(let len=deepthreads.length, i=0; i<len; ++i) { deepthreads[i].innerHTML = ''; } container.innerHTML = '';
removechild & appendChild(cloneNode())
// caching vars doubles bench speed. The length of the scope chain to access values from preparation is excessive const { container, deepthreads, pulsar, expand } = RESOURCES; for(let child, dt, len=deepthreads.length, i=0; i<len; ++i) { (dt = deepthreads[i]); while ((child=dt.lastChild)!==null) { child.remove(); } dt.appendChild(pulsar.cloneNode(true)); } for(let child, dt, len=deepthreads.length, i=0; i<len; ++i) { (dt = deepthreads[i]); while ((child=dt.lastChild)!==null) { child.remove(); } dt.appendChild(expand.cloneNode(true)); } for(let child, dt, len=deepthreads.length, i=0; i<len; ++i) { (dt = deepthreads[i]); while ((child=dt.lastChild)!==null) { child.remove(); } } for(let child; (child=container.lastChild)!==null; ) { child.remove() }
replaceChildren
// caching vars doubles bench speed. The length of the scope chain to access values from preparation is excessive const { container, deepthreads, pulsar, expand } = RESOURCES; for(let len=deepthreads.length, i=0; i<len; ++i) { deepthreads[i].replaceChildren(pulsar.cloneNode(true)); } for(let len=deepthreads.length, i=0; i<len; ++i) { deepthreads[i].replaceChildren(expand.cloneNode(true)); } for(let len=deepthreads.length, i=0; i<len; ++i) { deepthreads[i].replaceChildren(); } container.replaceChildren();
Custom deleteChildren
// caching vars doubles bench speed. The length of the scope chain to access values from preparation is excessive const { container, deepthreads, pulsar, expand, deleteChildren } = RESOURCES; for(let len=deepthreads.length, i=0; i<len; ++i) { deleteChildren(deepthreads[i]).appendChild(pulsar.cloneNode(true)); } for(let len=deepthreads.length, i=0; i<len; ++i) { deleteChildren(deepthreads[i]).appendChild(expand.cloneNode(true)); } for(let len=deepthreads.length, i=0; i<len; ++i) { deleteChildren(deepthreads[i]); } deleteChildren(container);
Custom replaceChildren via append
// caching vars doubles bench speed. The length of the scope chain to access values from preparation is excessive const { container, deepthreads, pulsar, expand, replaceChildren_append } = RESOURCES; for(let len=deepthreads.length, i=0; i<len; ++i) { replaceChildren_append(deepthreads[i], pulsar.cloneNode(true)); } for(let len=deepthreads.length, i=0; i<len; ++i) { replaceChildren_append(deepthreads[i], expand.cloneNode(true)); } for(let len=deepthreads.length, i=0; i<len; ++i) { replaceChildren_append(deepthreads[i]); } replaceChildren_append(container);
Custom replaceChildren via appendChild
// caching vars doubles bench speed. The length of the scope chain to access values from preparation is excessive const { container, deepthreads, pulsar, expand, replaceChildren_appendChild } = RESOURCES; for(let len=deepthreads.length, i=0; i<len; ++i) { replaceChildren_appendChild(deepthreads[i], pulsar.cloneNode(true)); } for(let len=deepthreads.length, i=0; i<len; ++i) { replaceChildren_appendChild(deepthreads[i], expand.cloneNode(true)); } for(let len=deepthreads.length, i=0; i<len; ++i) { replaceChildren_appendChild(deepthreads[i]); } replaceChildren_appendChild(container);

Run results for: innerHTML vs replaceChildren() vs removeChild()|appendChild(cloneNode())

innerHTML

removechild & appendChild(cloneNode())

replaceChildren

Custom deleteChildren

Custom replaceChildren via append

Custom replaceChildren via appendChild