Benchmark: Pre-array or function calls

Script Preparation code:


var xOffset = 0;
var xScale = 1;
var i = 0, l = 10000000;

function getX( index ) {
  return xOffset + index * xScale;
}

var tot = 0;

Tests:

test1
for( ;i < l; i ++ ) { tot += this.getX( i ); }
test2
for( ;i < l; i ++ ) { tot += xOffset + i * xScale; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
test1
test2

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

This benchmark does not have any results yet. Be the first one to run it!

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

LLMs can make mistakes. Check important info.

**Benchmark Overview**

The provided JSON represents a JavaScript microbenchmark created on MeasureThat.net. The benchmark measures the performance difference between two approaches: calling a function with `this` and accessing variables without it.

**Script Preparation Code**

The script preparation code is a JavaScript snippet that initializes several variables:
```javascript
var xOffset = 0;
var xScale = 1;
var i = 0, l = 10000000;

function getX(index) {
  return xOffset + index * xScale;
}

var tot = 0;
```
These variables are used in the benchmark test cases.

**Html Preparation Code**

The HTML preparation code is empty in this case, indicating that no specific HTML structure or content is being tested.

**Individual Test Cases**

There are two test cases:

1. **test1**

Benchmark Definition:
```javascript
for ( ; i < l; i ++ ) {
  tot += this.getX( i );
}
```
This test case calls the `getX` function with `this` and adds the result to a running total.

Pros of using `this` in `test1`:

* Easy to read and maintain code
* No need to explicitly pass the object as an argument

Cons of using `this` in `test1`:

* May lead to unexpected behavior if the function is called without context (e.g., as a standalone function)
* Can be slower due to the overhead of resolving the `this` binding

2. **test2**

Benchmark Definition:
```javascript
for ( ; i < l; i ++ ) {
  tot += xOffset + i * xScale;
}
```
This test case accesses the variables directly without using `this`.

Pros of accessing variables directly in `test2`:

* Generally faster than calling a function with `this`
* More explicit and less prone to errors

Cons of accessing variables directly in `test2`:

* Requires manual handling of variable scoping
* Can lead to more complex code if not done carefully

**Library**

None is explicitly mentioned, but it appears that MeasureThat.net uses a standard JavaScript environment.

**Special JS Feature/Syntax**

There is no mention of any special JavaScript features or syntax being used in this benchmark. The focus is on the performance difference between two approaches to accessing variables.

**Alternatives**

Other alternatives for measuring performance differences in JavaScript might include:

* Using `console.time` and `console.timeEnd` to measure execution time
* Implementing a microbenchmarking framework like Jest's ` Benchmark`
* Using a profiling tool like Chrome DevTools' Performance Tab

Keep in mind that MeasureThat.net is specifically designed for benchmarking JavaScript code, so it may not be the best choice for all use cases.

Related benchmarks:

Pre-array or function calls (version: 0)

Comparing performance of: test1 vs test2

Created: 9 years ago by: Guest

Jump to the latest result

test1

test2

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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