Benchmark: arr = [] or arr.length=0

Script Preparation code:

var arr=[];
for(i=0; i<10; i++){
  arr.push(i);
  arr=[];
}

Tests:

length 0
var arr=[]; for(i=0; i<1000; i++){ arr.length=0; arr.push(i); } console.log(arr);
asd
var arr=[]; for(i=0; i<1000; i++){ arr=[]; arr.push(i); } console.log(arr);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
length 0
asd

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

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

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

The provided JSON represents two JavaScript microbenchmarks that test the performance of array operations in JavaScript. The benchmarks are:

1. `arr = [] or arr.length=0`: This test checks how long it takes to create an empty array (`var arr=[];`) and then push elements into it (`for(i=0; i<10; i++){ arr.push(i); arr=[]; }`).
2. `length 0`: This test is a variation of the first one, but with some differences in the script preparation code (`var arr=[]; for(i=0; i<1000; i++){ arr.length=0; arr.push(i); } console.log(arr);`) and test name (`"Test Name": "length 0"`).

**Options compared**

The two benchmarks compare different approaches to array operations:

1. **Pushing elements into an empty array**: The first benchmark creates an empty array and pushes elements into it, while the second one uses `arr.length=0` to reset the length of the array before pushing new elements.
2. **Resetting array length vs. reassigning array**: In the second test, the script preparation code assigns a new value to `arr.length` instead of creating a new array using `var arr=[];`. This is an interesting choice, as it can affect performance.

**Pros and Cons**

* **Pushing elements into an empty array**:
	+ Pros: Easy to understand and implement.
	+ Cons: May be slower due to the repeated push operations.
* **Resetting array length vs. reassigning array**:
	+ Pros: Could potentially be faster, as it avoids creating a new array object.
	+ Cons: Less intuitive for readers, and may not perform well in all scenarios.

**Library usage**

There is no explicit library mentioned in the provided JSON. However, the use of `console.log` suggests that the test might rely on the global console API.

**Special JS feature or syntax**

The tests do not explicitly use any special JavaScript features or syntax. However, the use of `var arr=[];` and `arr.length=0` could be considered a stylistic choice, as modern JavaScript would typically recommend using `let arr = [];` and `arr.length = 0;`.

**Other alternatives**

If you wanted to modify these benchmarks, here are some alternative approaches:

1. **Use modern array methods**: Instead of pushing elements into an empty array, you could use the `push()` method with a new array object: `var arr=[]; for(i=0; i<10; i++){ arr.push([i]); }`.
2. **Use a different data structure**: You could test the performance of using other data structures, such as linked lists or objects.
3. **Add more complexity to the script preparation code**: You could introduce additional operations, such as iterating over an array and pushing new elements into it, or use more complex data structures.

Keep in mind that the goal of a benchmark is often to identify performance bottlenecks or areas for optimization. By modifying these benchmarks, you can explore different approaches and determine which ones perform best in your specific use case.

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/79.0.3945.130 Safari/537.36

Browser/OS: Chrome 79 on Windows

View result in a separate tab

Test name	Executions per second
length 0	12064.0 Ops/sec
asd	27025.8 Ops/sec

Related benchmarks:

arr = [] or arr.length=0 (version: 0)

test

Comparing performance of: length 0 vs asd

Created: 4 years ago by: Guest

Jump to the latest result

length 0

asd

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):