Benchmark: DataView vs Uint8Array by bytes vs Uint8Array set Uint8Array vs DataView loop

Script Preparation code:

var size = 0xFF;
var buf = new ArrayBuffer(size);
var view = new DataView(buf);
var byte = new Uint8Array(buf);

var data = [];

for (let i = 0; i < size; i++) {
    data[i] = 100 * Math.random();
}

var dataBytes = new Uint8Array(data);
var dataView = new DataView(dataBytes.buffer);

Tests:

DataView
for (let i; i < size; i++) { view.setUint8(i, data[i]); }
Uint8Array by byte
for (let i; i < size; i++) { byte[i] = data[i]; }
Uint8Array with set
byte.set(data, 0);
Uint8Array with set other Uint8Array
byte.set(dataBytes, 0);
DataView loop
for (let i = 0; i < dataBytes.length; i++) { view.setUint8(i, dataView.getUint8(i)); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
DataView
Uint8Array by byte
Uint8Array with set
Uint8Array with set other Uint8Array
DataView loop

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

**What is being tested?**

The provided JSON represents a benchmark test case that compares the performance of different approaches for setting values in Uint8Array and DataView objects.

Specifically, four test cases are defined:

1. **DataView**: Setting values directly using `view.setUint8(i, data[i])`.
2. **Uint8Array by byte**: Setting values directly using `byte[i] = data[i]`.
3. **Uint8Array with set**: Using the `set` method on a Uint8Array object to set values.
4. **Uint8Array with set other Uint8Array**: Using the `set` method on another Uint8Array object to set values.

**Options compared:**

The test compares two main options:

* Direct assignment using `byte[i] = data[i]` (Uint8Array by byte).
* Using the `set` method on a Uint8Array object (Uint8Array with set).

Both approaches have their pros and cons:

* **Direct assignment**: Fast and straightforward, but may involve more CPU cycles due to the overhead of assigning values.
* **Using the `set` method**: More efficient than direct assignment, as it allows the browser's optimized code path to handle the assignment.

**Other considerations:**

The test also compares two variations of the Uint8Array with set approach:

* Using a different Uint8Array object (`byte.set(dataBytes, 0)`).
* Using the `set` method on the original Uint8Array object (`byte.set(data, 0)`).

These variations may impact performance due to differences in memory allocation and caching.

**Library:**

The test uses two built-in JavaScript libraries:

1. **ArrayBuffer**: Creates a buffer for storing data.
2. **Uint8Array**: Represents an array of unsigned 8-bit integers.
3. **DataView**: Provides an interface for accessing the contents of an ArrayBuffer or typed array.

These libraries are essential components of the benchmark test, as they enable the creation and manipulation of binary data in JavaScript.

**Special JS feature or syntax:**

The test does not use any special JavaScript features or syntax, other than the use of `let` and `const` for variable declarations. No advanced techniques like closures, async/await, or Promises are employed.

**Alternatives:**

Other alternatives to consider for benchmarking similar scenarios:

1. **Native array types**: Using native array types (e.g., Int8Array) instead of Uint8Array.
2. ** typed arrays with specific byte orders**: Comparing performance using different typed arrays (e.g., Uint16Array, Uint32Array).
3. **Buffer objects**: Using Buffer objects from the `buffer` module to store and manipulate binary data.

Note that these alternatives may require modifications to the benchmark test code to accommodate the new APIs or libraries being used.

Latest run results:

Run details: (Test run date: 10 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.36

Browser/OS: Chrome 119 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
DataView	16785614.0 Ops/sec
Uint8Array by byte	16854644.0 Ops/sec
Uint8Array with set	1505970.6 Ops/sec
Uint8Array with set other Uint8Array	8216158.5 Ops/sec
DataView loop	23775.2 Ops/sec

Related benchmarks:

DataView vs Uint8Array by bytes vs Uint8Array set Uint8Array vs DataView loop (version: 0)

Comparing performance of: DataView vs Uint8Array by byte vs Uint8Array with set vs Uint8Array with set other Uint8Array vs DataView loop

Created: 2 years ago by: Guest

Jump to the latest result

DataView

Uint8Array by byte

Uint8Array with set

Uint8Array with set other Uint8Array

DataView loop

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):