Benchmark: Object property assign vs Object.assign performance

Tests:

Using property assign
const firstObject = { sampleData: 'Hello world' } firstObject.moreData = 'foo bar';
Using Object.assign
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } Object.assign(firstObject, secondObject);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Using property assign
Using Object.assign

Fastest: N/A

Slowest: N/A

Latest run results:

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Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

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Let's break down the provided benchmark and explain what's being tested.

**Benchmark Overview**

The benchmark compares the performance of two approaches for assigning additional properties to an object:

1. **Property assign**: Directly setting properties on the `firstObject` using dot notation (e.g., `firstObject.moreData = 'foo bar';`).
2. **Object.assign**: Using the `Object.assign()` method to copy properties from another object (`secondObject`) and assign them to `firstObject`.

**Options Compared**

The benchmark tests two options:

1. Property assign: Directly setting properties on the object.
2. Object.assign: Using the `Object.assign()` method.

**Pros and Cons of Each Approach**

* **Property Assign**:
	+ Pros:
		- Simple, intuitive syntax
		- Fast and efficient since it only involves accessing and modifying existing memory locations.
	+ Cons:
		- May be slower due to the overhead of calculating property names and resolving them to indices in the object's internal hash table.
* **Object.assign**:
	+ Pros:
		- Often faster, especially for large objects or when assigning many properties at once.
		- Avoids the overhead of calculating property names and resolving them to indices in the object's internal hash table.
	+ Cons:
		- Requires creating a new array or object with `Object.assign()`, which can add additional memory allocation and copying.

**Other Considerations**

* Both approaches have a relatively low overhead, making the performance difference between them likely to be small for most use cases.
* The benchmark may not capture the nuances of modern JavaScript engines' optimizations, such as tail call elimination or inlining.
* This benchmark does not account for factors like caching, garbage collection, or other system-level effects that might impact performance.

**Library Usage**

There is no explicit library usage mentioned in this benchmark. However, some JavaScript engines may use internal libraries or optimized implementations of `Object.assign()` under the hood.

**Special JS Features/Syntax**

This benchmark does not use any special JavaScript features or syntax beyond standard language elements like object literals and property assignment.

**Alternatives**

If you're looking for alternative benchmarks that compare performance optimization techniques, consider the following:

* The Google Benchmark library provides a comprehensive set of benchmarks for various programming languages and frameworks.
* The JSPerf benchmarking tool is another popular option for comparing JavaScript performance.
* The V8 Profiler, developed by the Chromium team, allows you to analyze and optimize the performance of your JavaScript code.

Keep in mind that these alternatives might have different focus areas or testing methodologies compared to MeasureThat.net's approach.

Related benchmarks:

Object property assign vs Object.assign performance (version: 0)

Comparing performance of: Using property assign vs Using Object.assign

Created: 5 years ago by: Guest

Jump to the latest result

Using property assign

Using Object.assign

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):