Benchmark: Encode vs Blob v2

Script Preparation code:

iterations = 1000;
function randomStringGen(n) {
    let strings = [];
    for (let i = 0; i < n; i++) {
      let s = Math.random().toString(36).substring(2, 15) + Math.random().toString(36).substring(2, 15);
      strings[i] = s;
    }
    return strings;
}
var randomStrings = randomStringGen(iterations);
var encoder = new TextEncoder();

Tests:

TextEncoder
var j = 0; for (let i = 0; i < iterations; i++) { var str = randomStrings[i % iterations]; new TextEncoder().encode(str).length }
Blob
var j = 0; for (let i = 0; i < iterations; i++) { var str = randomStrings[i % iterations]; new Blob([str]).size }
Buffer.byteLength
var j = 0; for (let i = 0; i < iterations; i++) { var str = randomStrings[i % iterations]; new Blob([str]).size }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
TextEncoder
Blob
Buffer.byteLength

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.3.1 Safari/605.1.15

Browser/OS: Safari 18 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
TextEncoder	5543.5 Ops/sec
Blob	30.6 Ops/sec
Buffer.byteLength	29.7 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks!

**Benchmark Overview**

The provided benchmark is called "Encode vs Blob v2". It tests the performance of three different approaches to measure the size of a string:

1. `TextEncoder`
2. `Blob`
3. `Buffer.byteLength`

**Script Preparation Code**

The script preparation code generates an array of random strings using the `randomStringGen` function, which creates strings by concatenating two random hexadecimal strings. This function is used to generate input data for the benchmark.

**Html Preparation Code**

There is no HTML preparation code provided.

**Individual Test Cases**

There are three test cases:

1. **TextEncoder**
```javascript
var j = 0;
for (let i = 0; i < iterations; i++) {
    var str = randomStrings[i % iterations];
    new TextEncoder().encode(str).length
}
```
This test case uses the `TextEncoder` API to measure the size of each input string.

2. **Blob**
```javascript
var j = 0;
for (let i = 0; i < iterations; i++) {
    var str = randomStrings[i % iterations];
    new Blob([str]).size
}
```
This test case uses the `Blob` constructor to create a blob from each input string and measures its size.

3. **Buffer.byteLength**
```javascript
var j = 0;
for (let i = 0; i < iterations; i++) {
    var str = randomStrings[i % iterations];
    new Blob([str]).size
}
```
This test case is actually identical to the `Blob` test case, as it also uses the `Blob` constructor and measures its size. It appears that there was a mistake in the original benchmark definition.

**Library and Purpose**

* **TextEncoder**: The `TextEncoder` API provides a way to efficiently encode strings into an array of bytes. In this benchmark, it's used to measure the size of each input string.
* **Blob**: The `Blob` constructor creates a blob from a sequence of byte-like values (such as strings). In this benchmark, it's used to create blobs from the input strings and measure their size.

**Special JS Features**

There are no special JavaScript features or syntax mentioned in the benchmark definition. It only uses standard JavaScript APIs and functions.

**Other Considerations**

* The benchmark uses a small number of iterations (1000) to generate random strings, which may not be representative of real-world usage.
* The benchmark is running on a mobile device with Safari 18, which may have different performance characteristics compared to other browsers or devices.

**Alternatives**

There are several alternatives for measuring the size of strings in JavaScript:

1. **`length` property**: Using the `length` property directly on a string object can provide a quick estimate of its length.
2. **`String.prototype.length`**: Using the `length` property on a string object is similar to using the `length` property directly on the string object.
3. **`Buffer.byteLength()`**: This function, also mentioned in the benchmark definition, provides an alternative way to measure the size of a string by creating a buffer and setting its length.

Keep in mind that these alternatives may not be as efficient or accurate as using the `TextEncoder` API or the `Blob` constructor.

Related benchmarks:

Encode vs Blob v2 (version: 0)

Comparing performance of: TextEncoder vs Blob vs Buffer.byteLength

Created: one year ago by: Guest

Jump to the latest result

TextEncoder

Blob

Buffer.byteLength

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):