Benchmark: Transform: Object.fromEntries vs reduce (small dataset)

Script Preparation code:

var ENTRIES = 10000;
var data = Array.from(Array(ENTRIES).keys()).map(key => ({id: key, someProp: key + 1}))
var createObject = (value) => ({ id: value.id });

Tests:

Object.fromEntries (with transform data)
Object.fromEntries( data.map( currentObj => { const transformedObj = createObject( currentObj ); return [ transformedObj.id, transformedObj ]; }));
Reduce (reuse object)
data.reduce( ( acc, currentObj ) => { const transformedObj = createObject( currentObj ); acc[ transformedObj.id ] = transformedObj; return acc; }, {});
Reduce (creating temporary objects)
data.reduce( ( acc, currentObj ) => { const transformedObj = createObject( currentObj ); return { ...acc, [ transformedObj.id ]: transformedObj }; }, {} );

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Object.fromEntries (with transform data)
Reduce (reuse object)
Reduce (creating temporary objects)

Fastest: N/A

Slowest: N/A

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/131.0.0.0 Safari/537.36

Browser/OS: Chrome 131 on Linux

View result in a separate tab

Test name	Executions per second
Object.fromEntries (with transform data)	2076.1 Ops/sec
Reduce (reuse object)	13022.5 Ops/sec
Reduce (creating temporary objects)	96.0 Ops/sec

Related benchmarks:

Transform: Object.fromEntries vs reduce (small dataset) (version: 0)

Comparing performance of: Object.fromEntries (with transform data) vs Reduce (reuse object) vs Reduce (creating temporary objects)

Created: 2 years ago by: Guest

Jump to the latest result

Object.fromEntries (with transform data)

Reduce (reuse object)

Reduce (creating temporary objects)

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A