Benchmark: Copy to float32Array

Script Preparation code:

var objectItem = {
  a:1,
  b:2,
  c:3,
}

var arrayItem = new Float32Array([1,2,3]);

var output = new Float32Array(300);

Tests:

copy from object
var index = 0; for(var i = 0; i < 300/3; i++) { output[index++] = objectItem.a; output[index++] = objectItem.b; output[index++] = objectItem.c; }
copy from floatArray
var index = 0; for(var i = 0; i < 300/3; i++) { output[index++] = arrayItem[0]; output[index++] = arrayItem[1]; output[index++] = arrayItem[2]; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
copy from object
copy from floatArray

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 months ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:147.0) Gecko/20100101 Firefox/147.0

Browser/OS: Firefox 147 on Linux

View result in a separate tab

Test name	Executions per second
copy from object	3441847.2 Ops/sec
copy from floatArray	3711638.0 Ops/sec

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

LLMs can make mistakes. Check important info.

**Benchmark Overview**

The provided benchmark is designed to measure the performance of two different approaches for copying data from an object or a Float32Array to another Float32Array. The benchmark consists of three parts:

1. **Script Preparation Code**: This section sets up the necessary variables, including `objectItem`, `arrayItem`, and `output`. It initializes `objectItem` with values 1, 2, and 3, creates a new Float32Array `arrayItem` with values 1, 2, and 3, and initializes an empty Float32Array `output` to hold the copied data.
2. **Html Preparation Code**: This section is empty, which means that no HTML-related code or setup is required for this benchmark.
3. **Individual Test Cases**: These are two test cases that perform the copying operation using different approaches.

**Approach 1: Copying from Object**

The first test case copies data from `objectItem` to `output`. This approach uses the dot notation (`objectItem.a`) to access the values of `objectItem`.

Pros:

* Easy to read and understand
* Simple and straightforward implementation

Cons:

* May be slower due to the overhead of accessing properties on an object using dot notation.

**Approach 2: Copying from Float32Array**

The second test case copies data from `arrayItem` to `output`. This approach uses direct array indexing (`arrayItem[0]`, `arrayItem[1]`, etc.) to access the values of `arrayItem`.

Pros:

* Often faster than accessing properties on an object using dot notation
* Can be optimized for direct memory access

Cons:

* May require more manual effort and understanding of arrays and their indexing.

**Library Used**

None. This benchmark does not use any external libraries or frameworks.

**Special JavaScript Feature/Syntax**

None mentioned in the provided code snippet, but it's essential to note that some modern JavaScript features like `const`, `let`, and `var` declarations are used in this benchmark.

**Other Considerations**

When writing benchmarks like this, it's crucial to consider factors such as:

* **Memory allocation and deallocation**: Are there any significant memory allocations or deallocations during the copying process?
* **Cache behavior**: How do different approaches affect cache locality and coherence?
* **Branch prediction**: Do the test cases induce good branch prediction?

**Alternatives**

There are several alternatives to this benchmark, depending on the specific requirements of your testing scenario:

* Measure the performance of copying data from an array to another array using `Array.prototype.copyWithin()`.
* Compare the performance of different JavaScript engines (e.g., V8, SpiderMonkey) and Node.js implementations.
* Measure the performance of different approaches for larger datasets or more complex data structures.

Keep in mind that these alternatives may require modifications to the benchmark setup and test cases.

Related benchmarks:

Copy to float32Array (version: 0)

Comparing performance of: copy from object vs copy from floatArray

Created: 3 years ago by: Registered User

Jump to the latest result

copy from object

copy from floatArray

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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