Benchmark: assgn to array2 - MeasureThat.net

Tests:

arr0
var arr = []; var num = 90; arr[0] = num; console.log(arr);
create arr
var arr = []; var num = 90; arr = [num]; console.log(arr);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
arr0
create arr

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

I'd be happy to help you understand the JavaScript benchmark on MeasureThat.net.

**What is being tested?**

The provided JSON represents two individual test cases for a JavaScript microbenchmark. The tests are designed to measure the performance of assigning a value to an array in different ways.

**Test Case 1: "arr0"**

In this test case, an empty array `arr` is declared and then assigned the value `90`. The array is not initialized with any size or type, so JavaScript will dynamically allocate memory for it when you try to push the value. This means that the actual execution time of assigning a value to the array might be affected by the internal workings of the JavaScript engine.

**Test Case 2: "create arr"**

In this test case, an empty array `arr` is declared and then immediately reassigned with the value `[num]`. This approach ensures that the array is explicitly initialized with a size of 1, which can potentially improve performance compared to the dynamic allocation in Test Case 1.

**Comparison of options**

The two test cases compare different approaches to assigning values to an array:

* **Test Case 1 ("arr0")**: This approach relies on JavaScript's dynamic allocation mechanism for arrays.
	+ Pros: Simple and easy to understand, doesn't require explicit memory management.
	+ Cons: Can lead to slower performance due to the overhead of dynamic allocation.
* **Test Case 2 ("create arr")**: This approach explicitly initializes the array with a size of 1 using the syntax `[num]`.
	+ Pros: Potential performance improvement due to reduced overhead from dynamic allocation.
	+ Cons: May be more complex and harder to understand, requires explicit memory management.

**Other considerations**

* **Array initialization**: JavaScript arrays are initialized with default values (e.g., `[]` for an empty array). However, these initializations can affect the performance of your code, especially if you're using them extensively.
* **Memory allocation**: JavaScript engines have to manage memory allocation and deallocation efficiently. In Test Case 1, the dynamic allocation mechanism might lead to slower performance compared to explicit initialization like in Test Case 2.

**Library usage**

There is no library mentioned in the provided JSON. However, if you're using a specific library for array operations or other features, it's essential to understand how that library affects your benchmark results.

**Special JS feature/syntax**

There are no special JavaScript features or syntax mentioned in the provided JSON. The tests focus on comparing different approaches to assigning values to an array.

**Alternatives**

If you want to create alternative test cases for this benchmark, consider exploring other scenarios, such as:

* Comparing different data structures (e.g., `Array.prototype.push()`, `Array.prototype.splice()`)
* Investigating the performance impact of using typed arrays (e.g., `Int32Array`) or array views
* Examining the effects of array operations on different types of JavaScript engines (e.g., V8, SpiderMonkey)

Keep in mind that these alternative test cases should be designed to measure specific aspects of your code and should be relevant to your 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
arr0	123059.0 Ops/sec
create arr	123602.2 Ops/sec

Related benchmarks:

assgn to array2 (version: 1)

Comparing performance of: arr0 vs create arr

Created: 4 years ago by: Registered User

Jump to the latest result

arr0

create arr

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):