Benchmark: Array vs Typed Array vs Buffer Typed Array

Script Preparation code:

var size = 450000;
var buf = new ArrayBuffer(size);

var normalArray = new Array(size);
var arrayFromBuffer = new Uint8Array(buf);
var arrayWithoutBuffer = new Uint8Array(size);

Tests:

Array
for (i =0; i< size; i++){ normalArray[i] = 0; }
typed array from Buffer
for (i =0; i< size; i++){ arrayFromBuffer[i] = 0; }
typed Array no buffer
for (i =0; i< size; i++){ arrayWithoutBuffer[i] = 0; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array
typed array from Buffer
typed Array no buffer

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what is being tested, compared, and their pros and cons.

**Benchmark Overview**

The benchmark compares the performance of three types of arrays in JavaScript: regular arrays (Array), typed arrays from buffers (Uint8Array, which we'll assume is a 8-bit unsigned integer array for this explanation), and a plain typed array without a buffer (Uint8Array, with the same assumption as above).

**Benchmark Preparation Code**

The script preparation code creates three arrays:

* `normalArray`: a regular JavaScript array of size 450,000.
* `arrayFromBuffer`: a Uint8Array created from an ArrayBuffer of size 450,000. This is done by wrapping an existing ArrayBuffer in a new Uint8Array object.
* `arrayWithoutBuffer`: another Uint8Array of size 450,000, created without referencing an existing ArrayBuffer.

The script then populates each array with zeros using a loop that iterates from 0 to the array's length (size).

**Benchmark Test Cases**

There are three test cases:

1. **Array**: This test case measures the performance of the `normalArray`.
2. **Typed Array from Buffer**: This test case measures the performance of the `arrayFromBuffer`.
3. **Typed Array no buffer**: This test case measures the performance of the `arrayWithoutBuffer`.

**Comparison and Pros/Cons**

The three arrays are compared in terms of their ability to populate an array with zeros:

* **Regular Arrays (Array)**: In JavaScript, regular arrays are dynamically typed, which means they can grow or shrink in size at runtime. This leads to slower performance due to the overhead of dynamic type checking.
* **Typed Arrays from Buffers (Uint8Array)**: Typed arrays, like Uint8Array, have a fixed size and type, which allows for faster execution because the JavaScript engine can optimize the code to perform operations directly on the typed array's buffer without the need for dynamic type checks. However, creating a new ArrayBuffer is an expensive operation, so this approach requires careful optimization.
* **Plain Typed Arrays without Buffer (Uint8Array)**: This test case uses Uint8Array objects created from existing arrays or other sources, which can provide faster performance than regular arrays because the JavaScript engine doesn't have to perform dynamic type checks.

**Library and Special Features**

The benchmark uses the following libraries:

* None explicitly mentioned, but it's likely that the benchmark uses built-in JavaScript features like `ArrayBuffer`, `Uint8Array`, and the `new` keyword for object creation.
* No special JS feature or syntax is used in this benchmark.

**Other Alternatives**

If you wanted to compare these arrays using a different approach:

* You could use native code (e.g., C++ or Rust) to create arrays with similar properties, which would likely be faster than JavaScript arrays. However, this would require significant changes to the benchmark and might not run in most browsers.
* Another alternative is to use a library like WebAssembly (WASM) that allows you to compile performance-critical code into a binary format that can be executed by the browser.

Keep in mind that these alternatives would likely change the nature of the comparison, and the results might not be directly comparable to the JavaScript array tests.

Latest run results:

Run details: (Test run date: 22 days ago)

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:131.0) Gecko/20100101 Firefox/131.0

Browser/OS: Firefox 131 on Linux

View result in a separate tab

Test name	Executions per second
Array	141.7 Ops/sec
typed array from Buffer	146.1 Ops/sec
typed Array no buffer	144.3 Ops/sec

Related benchmarks:

Array vs Typed Array vs Buffer Typed Array (version: 0)

Comparing performance of: Array vs typed array from Buffer vs typed Array no buffer

Created: 3 years ago by: Guest

Jump to the latest result

Array

typed array from Buffer

typed Array no buffer

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):