Benchmark: copy copy copy copy copy

Script Preparation code:

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

Tests:

view.setUint8(i, data[i]);
for (let i=0; i < size; i++) { view.setUint8(i, data[i]); }
byte[i] = data[i];
for (let i=0; i < size; i++) { byte[i] = data[i]; }
byte.set(data);
byte.set(data);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
view.setUint8(i, data[i]);
byte[i] = data[i];
byte.set(data);

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's break down the provided JSON benchmark definition and individual test cases.

**Benchmark Definition**

The provided JSON represents a JavaScript microbenchmark for copying large arrays of numbers between different JavaScript data types:

1. `DataView`: A binary view of an ArrayBuffer, allowing direct access to its contents.
2. `Uint8Array` (or simply `byte`): An array of unsigned 8-bit integers.
3. `Uint8Array` again (`data`): Another copy of the same array.

The script preparation code initializes:

* `size`: The size of the ArrayBuffer, set to a large value (0xFFFF).
* `buf`: A new ArrayBuffer with the specified size.
* `view`: A DataView instance created from the `buf`.
* `byte`: A new Uint8Array view of the `buf`.

The script also creates another array (`data`) and fills it with random numbers.

**Options Compared**

Three different approaches are compared:

1. `view.setUint8(i, data[i]);`
2. `byte[i] = data[i];` (direct assignment)
3. `byte.set(data);` (using the `set()` method)

These approaches differ in how they access and manipulate the array elements.

**Pros and Cons**

Here's a brief summary of each approach:

1. `view.setUint8(i, data[i]);`
	* Pros:
		+ Directly accesses the ArrayBuffer using a DataView.
		+ May be more efficient for large arrays due to reduced memory allocation and deallocation.
	* Cons:
		+ Requires a DataView instance, which may add overhead.
		+ Can be slower due to the additional step of setting each element individually.
2. `byte[i] = data[i];` (direct assignment)
	* Pros:
		+ Fast and simple assignment.
		+ Does not require any additional libraries or objects.
	* Cons:
		+ Inefficient for large arrays since it involves assigning each element individually.
3. `byte.set(data);`
	* Pros:
		+ Fast and efficient, as it uses the `set()` method to set all elements at once.
	* Cons:
		+ Requires a Uint8Array instance and may not work correctly if the input array has different length.

**Library Usage**

The benchmark uses two JavaScript libraries:

1. `DataView`: A built-in library for working with binary data in JavaScript.
2. `Uint8Array` (or simply `byte`): Built-in, no additional library needed.

No external libraries are used for this specific benchmark.

**Special JS Features/Syntax**

This benchmark does not use any special JavaScript features or syntax beyond what is required to access and manipulate arrays. However, it does utilize:

1. `for...of` loops (not explicitly shown but implied by the array assignments).
2. `let` declaration (used for variable declarations).

**Alternatives**

If you wanted to test similar benchmarks with alternative approaches, consider the following:

1. Using other libraries or frameworks that provide optimized implementations for copying arrays.
2. Implementing your own custom copy function using bitwise operations or other low-level techniques.
3. Comparing different data types, such as `Float32Array`, `Int8Array`, or even typed arrays like `Float64Array`.
4. Experimenting with parallel processing or concurrent execution to see if it improves performance.

Keep in mind that the choice of approach and libraries can significantly impact the benchmark's results and relevance.

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/107.0.0.0 Safari/537.36 Edg/107.0.1391.0

Browser/OS: Chrome 107 on Windows

View result in a separate tab

Test name	Executions per second
view.setUint8(i, data[i]);	33.2 Ops/sec
byte[i] = data[i];	36.6 Ops/sec
byte.set(data);	503381.9 Ops/sec

Related benchmarks:

copy copy copy copy copy (version: 0)

copy

Comparing performance of: view.setUint8(i, data[i]); vs byte[i] = data[i]; vs byte.set(data);

Created: 2 years ago by: Guest

Jump to the latest result

view.setUint8(i, data[i]);

byte[i] = data[i];

byte.set(data);

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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