Benchmark: set in loop vs at the end

Tests:

Set in the loop
const dataset = {data:[]}; for(var i=0; i<1000; i++){ dataset.data = [...new Set([...dataset.data, i, (i+1)])]; }
set after the loop
const dataset = {data:[]}; for(var i=0; i<1000; i++){ dataset.data.push(i); dataset.data.push(i+1); } dataset.data = [...new Set([...dataset.data])]

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Set in the loop
set after the loop

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/83.0.4103.61 Safari/537.36

Browser/OS: Chrome 83 on Windows

View result in a separate tab

Test name	Executions per second
Set in the loop	55.7 Ops/sec
set after the loop	18985.2 Ops/sec

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

LLMs can make mistakes. Check important info.

I'll break down the provided benchmark and explain what's being tested, compared, and some considerations.

**Benchmark Definition JSON**

The benchmark definition is empty, which means that the actual script preparation code for each test case needs to be defined in the "Script Preparation Code" field. Since this information is not provided, I will explain the two test cases without it.

**Test Cases**

There are two individual test cases:

1. **Set in the loop**
```javascript
const dataset = {data:[]};
for(var i=0; i<1000; i++){
  dataset.data = [...new Set([...dataset.data, i, (i+1)])];
}
```

This test case is testing the performance of setting an element to a new array using the `Set` constructor. The loop iterates from 0 to 999 and on each iteration, it adds two elements (`i` and `i+1`) to the `dataset.data` array. Then, it creates a new set containing these elements and assigns it back to `dataset.data`.

2. **Set after the loop**
```javascript
const dataset = {data:[]};
for(var i=0; i<1000; i++){
  dataset.data.push(i);
  dataset.data.push(i+1);
}
dataset.data = [...new Set([...dataset.data])];
```

This test case is similar to the first one, but instead of adding elements directly to the array, it pushes two elements onto the end of the array. Then, after the loop finishes, it creates a new set containing all the elements in the `dataset.data` array and assigns it back.

**Options Compared**

The two test cases are comparing two different approaches:

* **Set in the loop**: adds elements directly to the array while iterating
* **Set after the loop**: adds elements onto the end of the array, then creates a new set containing all the elements

**Pros and Cons**

Both approaches have their pros and cons:

* **Set in the loop**:
	+ Pros: potentially faster since it avoids creating an intermediate array
	+ Cons: may involve more complex iteration logic and potential cache thrashing
* **Set after the loop**:
	+ Pros: simpler iteration logic, less chance of cache thrashing
	+ Cons: may be slower due to the creation of the intermediate array

**Library**

There is no library explicitly mentioned in the test cases. However, the `Set` constructor is a built-in JavaScript API.

**Special JS Features/Syntax**

None are mentioned.

**Other Considerations**

* Cache thrashing: creating and destroying arrays can lead to cache thrashing, which may impact performance.
* Intermediate array size: creating an intermediate array before setting elements can impact performance if the array is large.
* Loop iteration logic: the order in which elements are added or processed within the loop can impact performance.

**Alternatives**

Other approaches that could be compared include:

* Using `map()` to create a new array with transformed elements
* Using `forEach()` to iterate over an array and process elements sequentially
* Using native Web APIs like WebGL for parallelized computation (if applicable)
* Optimizing specific parts of the code, such as minimizing memory allocation or optimizing branching logic

Keep in mind that these alternatives may not be relevant depending on the specific requirements and constraints of the benchmark.

Related benchmarks:

set in loop vs at the end (version: 0)

Comparing performance of: Set in the loop vs set after the loop

Created: 4 years ago by: Guest

Jump to the latest result

Set in the loop

set after the loop

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):