Benchmark: arr delete: length=0 vs []

Tests:

length
var arr = [1, 2, 3, 4]; arr.length = 0;
other
var arr = [1, 2, 3, 4]; arr = [];

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
length
other

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 9 months ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/138.0.0.0 Safari/537.36 Edg/138.0.0.0

Browser/OS: Chrome 138 on Windows

View result in a separate tab

Test name	Executions per second
length	52797072.0 Ops/sec
other	235582736.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down what's being tested in the provided benchmark.

**What is being measured?**

The test case measures the performance of two different approaches to resetting an array to an empty state: setting `arr.length = 0` or using the assignment operator `arr = []`.

**Options compared:**

There are two options being compared:

1. **`arr.length = 0`**: This approach sets the length property of the array to 0, effectively reducing its size.
2. **`arr = []`**: This approach reassigns the entire array to a new empty array.

**Pros and cons of each approach:**

* **`arr.length = 0`**:
	+ Pros:
		- Generally faster, as it only updates the length property without creating a new array.
		- Less memory allocation is required.
	+ Cons:
		- May not work correctly in some older browsers or with certain array implementations (e.g., `ArrayBuffer`).
* **`arr = []`**:
	+ Pros:
		- More straightforward and readable code.
		- Works consistently across all browsers and array implementations.
	+ Cons:
		- Generally slower, as it creates a new array object.

**Other considerations:**

When choosing between these two approaches, consider the specific requirements of your use case. If you need to iterate over the original array elements without modifying the array itself, using `arr = []` might be a better choice. However, if memory efficiency and speed are crucial, setting `arr.length = 0` is likely a better option.

**Library usage:**

There doesn't seem to be any specific library being used in these test cases.

**Special JavaScript features or syntax:**

None of the provided benchmark definitions use any special JavaScript features or syntax beyond standard array operations.

Related benchmarks:

arr delete: length=0 vs [] (version: 0)

Comparing performance of: length vs other

Created: 6 years ago by: Guest

Jump to the latest result

length

other

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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