Benchmark: reverse - MeasureThat.net

Tests:

temp swap
let arr = [1,4,6] let len = arr.length let temp = 0 for(let i=0; i<Math.floor(arr.length/2); i++){ let x = i let y = len-1-i temp = arr[x] arr[x] = arr[y] arr[y] = temp } console.log(arr)
xor swap
let arr = [1,4,6] let len = arr.length for(let i=0; i<Math.floor(arr.length/2); i++){ let x = i let y = len-1-i arr[x] = arr[x] ^ arr[y] arr[y] = arr[x] ^ arr[y] arr[x] = arr[x] ^ arr[y] } console.log(arr)
inbuilt
let arr= [1,2,3] arr.reverse()
manual rvers
let arr=[1,2,3], res =[] for(let i=arr.length-1; i>=0; i--) { res = arr[i] } console.log(res)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
temp swap
xor swap
inbuilt
manual rvers

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 27 days ago):

LLMs can make mistakes. Check important info.

Let's break down the benchmark and its various components.

**Benchmark Definition**

The provided JSON represents a JavaScript microbenchmark, which is a test designed to measure the performance of specific code snippets. The benchmark definition includes the following elements:

* `Name`: A unique name for the benchmark, in this case, "reverse".
* `Description`: An optional description of the benchmark, but none is provided.
* `Script Preparation Code` and `Html Preparation Code`: These are empty strings, indicating that no specific code needs to be executed before running the benchmark. This might be used if the benchmark only requires a minimal setup.

**Individual Test Cases**

The benchmark consists of four test cases:

1. **temp swap**: This test case involves swapping elements in an array using a temporary variable.
2. **xor swap**: Similar to the first test case, but uses bitwise XOR operations to swap elements.
3. **inbuilt**: This test case uses the built-in `reverse()` method of arrays to reverse their order.
4. **manual rvers**: This test case reverses an array manually by iterating over its elements and appending them in reverse order.

**Options Compared**

The benchmark compares four different approaches for reversing an array:

1. **temp swap**: Uses a temporary variable to swap elements in the array.
2. **xor swap**: Utilizes bitwise XOR operations to achieve element swapping.
3. **inbuilt**: Leverages the built-in `reverse()` method provided by JavaScript engines.
4. **manual rvers**: Implements a manual reversal approach using iteration and concatenation.

**Pros and Cons of Each Approach**

Here's a brief analysis of each approach:

* **temp swap**: Pros: Simple, well-known algorithm. Cons: Requires extra memory for the temporary variable and can lead to cache locality issues.
* **xor swap**: Pros: Can be more efficient in terms of cache access patterns due to its bitwise nature. Cons: May require additional cycles due to the XOR operations, and some CPU architectures may not support XOR swaps.
* **inbuilt**: Pros: Fastest implementation, optimized by JavaScript engines. Cons: Not a traditional "algorithm" but rather an inherent feature of JavaScript.
* **manual rvers**: Pros: Can be more predictable and cache-friendly than other approaches. Cons: More complex to implement and may require more iterations due to the manual reversal.

**Library Usage**

None of the test cases explicitly use any external libraries, but they do rely on built-in JavaScript methods like `reverse()`.

**Special JS Features or Syntax**

There are no notable special features or syntax used in these benchmarks, except for the use of bitwise XOR operations (`^`) in the `xor swap` approach. This is a basic operation in many programming languages and is not unique to JavaScript.

**Other Alternatives**

If you were looking for alternative approaches to reverse an array, some possible options could be:

* Using a recursive function
* Implementing a linked list reversal algorithm
* Utilizing assembly language or low-level optimizations (not recommended due to platform and compiler dependencies)
* Leveraging parallel processing or multi-threading techniques (if available)

Keep in mind that these alternatives would likely have different performance characteristics, trade-offs, and complexity levels.

I hope this explanation helps you understand the benchmark and its various components!

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/106.0.0.0 Safari/537.36

Browser/OS: Chrome 106 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
temp swap	123531.7 Ops/sec
xor swap	107936.8 Ops/sec
inbuilt	42128328.0 Ops/sec
manual rvers	169890.8 Ops/sec

Related benchmarks:

reverse (version: 0)

Comparing performance of: temp swap vs xor swap vs inbuilt vs manual rvers

Created: 3 years ago by: Guest

Jump to the latest result

temp swap

xor swap

inbuilt

manual rvers

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 27 days ago):