Benchmark: Array sift test - MeasureThat.net

Tests:

unsift array
let arr = Array.from(Array(1000).keys()) for(i=0; i<1000; i++){ arr.unshift(i); } console.log(arr);
spread array
let arr = Array.from(Array(1000).keys()) for(i=0; i<1000; i++){ arr = [i, ...arr]; } console.log(arr);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
unsift array
spread array

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36

Browser/OS: Chrome 126 on Windows

View result in a separate tab

Test name	Executions per second
unsift array	2801.5 Ops/sec
spread array	202.1 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 MeasureThat.net and explore what's being tested in this specific benchmark.

**Benchmark Definition**
The benchmark is defined by a JSON object with four properties:

1. `Name`: A human-readable name for the benchmark, which is "Array sift test".
2. `Description`: An optional description of the benchmark, which is empty in this case.
3. `Script Preparation Code`: An optional code that's executed before running the benchmark, which is also empty in this case.
4. `Html Preparation Code`: Another optional code that's executed before running the benchmark, which is also empty.

These properties provide context for the benchmark but don't affect the actual testing process.

**Individual Test Cases**
The benchmark consists of two test cases:

1. **"unsift array"`**
This test case uses a simple JavaScript loop to append 1000 numbers to an array using `arr.unshift(i)`. The resulting array is then logged to the console.
2. **"spread array"`**
This test case also creates an array of 1000 numbers, but it uses the spread operator (`...`) to concatenate the new number with the existing array. The resulting array is then logged to the console.

**Library: None**
There are no libraries being used in this benchmark.

**Special JavaScript Features/ Syntax: None**
Neither test case uses any special JavaScript features or syntax that would affect its performance.

Now, let's discuss the pros and cons of each approach:

1. **Using `arr.unshift(i)`**:
	* Pros:
		+ Simple and straightforward.
	* Cons:
		+ Requiring a new element to be added at the beginning of the array, which can lead to unnecessary allocations and copying.
2. **Using the spread operator (`...`)**:
	* Pros:
		+ More efficient than `unshift`, as it avoids the need for multiple allocations and copies.
	* Cons:
		+ Requires a compatible browser or environment that supports the spread operator.

In general, using the spread operator is considered more efficient, but its performance benefits may be negligible in most cases. The benchmark results we have suggest that the `spread array` approach is slightly faster than the `unsift array` approach, which might be due to the reduced number of allocations and copies required.

**Other Alternatives**
If you were to modify or extend this benchmark, here are some alternative approaches you could consider:

* Using `Array.prototype.push()` with a for loop: `arr.push(i);`
	+ This approach is similar to the spread operator but uses the built-in `push` method instead.
* Using a custom implementation of an insertion algorithm (e.g., binary search): `arr.insert(i, index) => { ... }`
	+ This approach would require more complex logic and might not be worth it unless you're dealing with very large arrays.

Overall, MeasureThat.net provides a useful platform for comparing the performance of different JavaScript approaches to array manipulation. By analyzing this benchmark and its results, we can gain insights into the trade-offs involved in choosing between different methods.

Related benchmarks:

Array sift test (version: 0)

Comparing performance of: unsift array vs spread array

Created: one year ago by: Guest

Jump to the latest result

unsift array

spread array

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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