Benchmark: Test for - MeasureThat.net

Script Preparation code:

var arr = [];
  for (var i = 0; i < 1000; i++) {
    arr[i] = i;
  }

  function someFn(ix) {
    return ix * 5 + 1 / 3 * 8;
  }

Tests:

while
var l = arr.length; while(l--) { someFn(arr[l]); }
for
for (var i = 0; i < arr.length; i++) { someFn(arr[i]); }
while 2
var l = arr.length; while(l-- >= 0) { someFn(arr[l]); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
while
for
while 2

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

Let's break down the benchmark and analyze what's being tested.

**Benchmark Definition**

The benchmark is defined by two scripts: `Script Preparation Code` and `Html Preparation Code`. The `Script Preparation Code` defines an array `arr` with 1000 elements, and a function `someFn` that takes an index `ix` as input. The `Html Preparation Code` is empty, which suggests that this benchmark doesn't require any HTML-related tests.

**Individual Test Cases**

The benchmark has three individual test cases:

1. **"while"`**: This test case uses the while loop in the benchmark definition to iterate over the array `arr`. The condition for the while loop is `l-- >= 0`, which will execute until `l` reaches -1.
2. **"for"`**: This test case uses the for loop in the benchmark definition to iterate over the array `arr`. The syntax is slightly different from the while loop, with a explicit increment (`i++`) and a condition (`i < arr.length`).
3. **"while 2"`**: This test case is similar to the first one, but it uses an inclusive decrement in the while loop condition (`l-- >= 0`).

**Options Compared**

The benchmark compares three different approaches:

* While loop (Test Case "while")
* For loop (Test Case "for")
* Inclusive decrement while loop (Test Case "while 2")

These options are compared in terms of their performance.

**Pros and Cons**

Here's a brief analysis of the pros and cons of each approach:

* **While loop**: This approach can be beneficial when dealing with arrays or other data structures that require a simple iteration. However, it can lead to slower performance due to the overhead of decrementing the loop counter.
* **For loop**: This approach is generally faster than the while loop, as it eliminates the need for incrementing the loop counter. However, it requires more memory to store the loop variable and increment/decrement operations.
* **Inclusive decrement while loop**: This approach can provide better performance than a traditional while loop, especially when dealing with large arrays. The inclusive decrement allows the loop to stop earlier, reducing the number of iterations.

**Library and Special JS Features**

There is no explicit library mentioned in the benchmark definition or test cases. However, some JavaScript features might be used implicitly:

* The `var` keyword is used for variable declarations, which is a good practice in older JavaScript versions.
* The `===` operator is used for comparison, which is a standard JavaScript operator.

**Other Considerations**

When running this benchmark, it's essential to consider the following factors:

* Browser and OS compatibility: The benchmark results are provided for Chrome 56 on Mac OS X 10.12.1, so it's likely that the test environment is optimized for these platforms.
* Array size and performance: The benchmark defines an array with 1000 elements, which can impact performance due to memory allocation and deallocation.

**Alternatives**

Some alternative approaches or libraries could be used to optimize the while loop or for loop:

* Using `Array.prototype.forEach()` instead of a custom while loop
* Using `Array.prototype.map()` instead of a custom for loop
* Optimizing the `someFn` function using JIT compilation or other performance-enhancing techniques

However, these alternatives might not provide significant performance benefits over the original implementation.

Latest run results:

Run details: (Test run date: 7 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924.87 Safari/537.36

Browser/OS: Chrome 56 on Mac OS X 10.12.1

View result in a separate tab

Test name	Executions per second
while	6751.2 Ops/sec
for	4528.1 Ops/sec
while 2	6541.8 Ops/sec

Related benchmarks:

Test for (version: 0)

Comparing performance of: while vs for vs while 2

Created: 7 years ago by: Guest

Jump to the latest result

while

for

while 2

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):