Benchmark: subarray vs. constructor perf

Script Preparation code:

dat = new Uint8Array(1000000);

Tests:

1
dat.subarray(78);
2
new Uint8Array(dat, 78);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
1
2

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0.0.0 Safari/537.36

Browser/OS: Chrome 130 on Linux

View result in a separate tab

Test name	Executions per second
1	3977753.8 Ops/sec
2	1779.9 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks and explore what's being tested on MeasureThat.net.

**Benchmark Overview**

The provided benchmark is designed to compare the performance of two approaches:

1. `subarray` method: This method creates a new array from a portion of another array.
2. `constructor` method: This method creates a new instance of an array constructor.

**Options Compared**

The benchmark compares the performance of these two methods for creating a subarray with a specific starting index (78) in a large array (`dat`) that has 1,000,000 elements.

**Pros and Cons**

* **subarray method**:
	+ Pros: More intuitive and concise syntax. It's a standard JavaScript method.
	+ Cons: Might be slower due to the overhead of creating a new array.
* **constructor method**:
	+ Pros: Can potentially be faster since it avoids the overhead of creating a new array.
	+ Cons: Requires more code, making it less intuitive and concise.

**Library and Purpose**

The `Uint8Array` constructor is used in both benchmark cases. A `Uint8Array` is an array-like object that holds unsigned 8-bit integers (uints) values, which are often used for efficient numerical computations.

**Special JavaScript Features or Syntax**

There's no special JavaScript feature or syntax being tested in this benchmark. The focus is on comparing the performance of two different methods for creating a subarray.

**Other Alternatives**

While not explicitly compared in this benchmark, other alternatives for creating a subarray include:

* Using the `Array.prototype.slice()` method: This method creates a shallow copy of a portion of an array.
* Using the `Array.prototype.slice.call()` method: This method converts an array-like object into an array.

Keep in mind that these alternatives might have different performance characteristics compared to the `subarray` and `constructor` methods used in this benchmark.

I hope this explanation helps you understand what's being tested on MeasureThat.net!

Related benchmarks:

subarray vs. constructor perf (version: 0)

Comparing performance of: 1 vs 2

Created: 4 years ago by: Guest

Jump to the latest result

1

2

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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