Benchmark: Spread performances

Script Preparation code:

class X { uuid = "0123456789ABCDEF" }
x = new X()

var array1 = Array(1).fill(x)
var array10 = Array(10).fill(x)
var array100 = Array(100).fill(x)
var array500 = Array(500).fill(x)
var array1000 = Array(1000).fill(x)

Tests:

Array + 1
var array = [...array100, array1]
Array + 10
var array = [...array100, array10]
Array + 100
var array = [...array100, array100]
Array + 500
var array = [...array100, array500]
Array + 1000
var array = [...array100, array1000]

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Array + 1
Array + 10
Array + 100
Array + 500
Array + 1000

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

The provided JSON represents a JavaScript benchmark, specifically designed to measure the performance of array spread operations.

**What is tested on the provided JSON?**

The test cases compare different approaches to perform an array spread operation:

1. `var array = [...array100, array1]`
2. `var array = [...array100, array10]`
3. `var array = [...array100, array100]`
4. `var array = [...array100, array500]`
5. `var array = [...array100, array1000]`

Each test case creates an array by spreading a smaller array (`array1`, `array10`, `array100`, `array500`, or `array1000`) into the original large array (`array100`).

**Options compared:**

* Array spread operation (`...`)
* Concatenation using the `+` operator
* Using a library like Lodash's `concat` function (not explicitly mentioned in the JSON, but assumed to be used for comparison)

**Pros and Cons of different approaches:**

1. **Array spread operation (`...`)**
	* Pros:
		+ Fast and efficient
		+ Can handle large arrays with minimal memory allocation
	* Cons:
		+ May not be supported in older browsers or versions
2. **Concatenation using the `+` operator**
	* Pros:
		+ Widely supported across browsers and versions
		+ Easy to understand and implement
	* Cons:
		+ Can lead to performance issues for large arrays due to repeated memory allocation

**Library consideration:**

If a library like Lodash's `concat` function is used, it would be expected to provide an optimized implementation of the concatenation operation. However, the JSON does not explicitly mention this library.

**Special JS feature or syntax:**

There are no special JavaScript features or syntax mentioned in the provided JSON that require explanation.

**Other considerations:**

* The benchmark measures the execution speed (in executions per second) for each test case.
* The results suggest that the array spread operation is significantly faster than concatenation using the `+` operator, especially for larger arrays like `array1000`.

**Alternatives:**

If you want to compare other approaches or alternatives, some options could be:

1. Using a library like Lodash's `concat` function
2. Implementing a custom concatenation function using a more efficient algorithm
3. Comparing the performance of different array data structures (e.g., arrays vs. linked lists)
4. Measuring the performance of other JavaScript operations, such as indexing or slicing

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/76.0.3809.100 Safari/537.36

Browser/OS: Chrome 76 on Linux

View result in a separate tab

Test name	Executions per second
Array + 1	1043507.1 Ops/sec
Array + 10	1105072.5 Ops/sec
Array + 100	1082029.0 Ops/sec
Array + 500	1077187.6 Ops/sec
Array + 1000	1142472.0 Ops/sec

Related benchmarks:

Spread performances (version: 0)

Spread performances with array of 1, 10, 100, 500 and 1000 elements.

Comparing performance of: Array + 1 vs Array + 10 vs Array + 100 vs Array + 500 vs Array + 1000

Created: 4 years ago by: Guest

Jump to the latest result

Array + 1

Array + 10

Array + 100

Array + 500

Array + 1000

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):