Benchmark: getElementById vs HTML5 global variable based on id value

HTML Preparation code:

<table id="testTable">
</table>

Script Preparation code:

// some elemens without id
for(var i=0; i<5000; ++i)
  testTable.insertRow(-1).insertCell(-1).textContent = 'Row #'+i;

// some elements with id
var parent = testTable.parentElement;
for(var i=0; i<5000; ++i)
{
  var div = document.createElement('div');
  div.id = 'divBefore'+i;
  parent.insertBefore(div, testTable);
  
  div = document.createElement('div');
  div.id = 'divAfter'+i;
  parent.appendChild(div);
}

Tests:

getElementById each time
for(var i=0; i<10000; ++i) { var table = document.getElementById('testTable'); table.rows[0].cells[0].textContent = 'Test'; }
Own global variable
var table = document.getElementById('testTable'); for(var i=0; i<10000; ++i) { table.rows[0].cells[0].textContent = 'Test'; }
Own global variable with equal name
var testTable = document.getElementById('testTable'); for(var i=0; i<10000; ++i) { testTable.rows[0].cells[0].textContent = 'Test'; }
HTML5 global variable based on id value
for(var i=0; i<10000; ++i) { testTable.rows[0].cells[0].textContent = 'Test'; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
getElementById each time
Own global variable
Own global variable with equal name
HTML5 global variable based on id value

Fastest: N/A

Slowest: N/A

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Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/110.0.0.0 Safari/537.36

Browser/OS: Chrome 110 on Linux

View result in a separate tab

Test name	Executions per second
getElementById each time	175.3 Ops/sec
Own global variable	363.3 Ops/sec
Own global variable with equal name	347.1 Ops/sec
HTML5 global variable based on id value	86.3 Ops/sec

getElementById vs HTML5 global variable based on id value (version: 0)

https://html.spec.whatwg.org/#named-access-on-the-window-object

Comparing performance of: getElementById each time vs Own global variable vs Own global variable with equal name vs HTML5 global variable based on id value

Created: 7 years ago by: Guest

Jump to the latest result

getElementById each time

Own global variable

Own global variable with equal name

HTML5 global variable based on id value

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A