Benchmark: lvng array append

Tests:

index
var a = []; var testSize = 1000; var arraySize = 1000; for(var i=0; i<testSize; i++){ for(var j=0; j<arraySize; j++){ a[j] = j; } }
index with length
var a = []; var testSize = 1000; var arraySize = 1000; for(var i=0; i<testSize; i++){ for(var j=0; j<arraySize; j++){ a[a.length] = j; } }
push
var a = []; var testSize = 1000; var arraySize = 1000; for(var i=0; i<testSize; i++){ for(var j=0; j<arraySize; j++){ a.push(j); } }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
index
index with length
push

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 27 days ago):

LLMs can make mistakes. Check important info.

Measuring the performance of JavaScript array operations can be an interesting and complex task.

**Benchmark Definition:**
The provided Benchmark Definition json specifies three test cases for measuring the performance of appending elements to an array:

1. "index": Appends elements directly to the existing array using indexing (e.g., `a[j] = j;`).
2. "index with length": Appends elements to the end of the array and updates the `length` property manually (e.g., `a[a.length] = j;`).
3. "push": Uses the `push()` method to add elements to the end of the array.

**Options Comparison:**

1. **Indexing (`a[j] = j;`)**:
	* Pros:
		+ Fast and efficient, as it accesses the element by its index without incrementing the length.
		+ Can be faster for small arrays or those with contiguous data.
	* Cons:
		+ May lead to slower performance for larger arrays, as indexing can become less efficient due to the need to traverse the array to find the correct position.
2. **Updating `length` (`a[a.length] = j;`)**:
	* Pros:
		+ Can be faster for large arrays, as it updates the `length` property directly, which is typically a single cache line operation.
	* Cons:
		+ May incur additional overhead due to updating the `length` property, potentially slowing down performance.
3. **`push()` method**:
	* Pros:
		+ Typically faster for large arrays, as it uses optimized internal buffer management and caching.
	* Cons:
		+ May lead to slower performance for small arrays or those with sparse data.

**Other Considerations:**

1. **Array initialization**: The benchmark assumes an empty array (`var a = [];`). In practice, you may want to consider initializing the array with some initial data or using `Array.from()` to create a new array.
2. **Data distribution**: The benchmark uses simple incrementing data (e.g., `j`) for appending elements. You may want to test more complex data distributions to see how they affect performance.

**Library and Purpose:**
In the provided Benchmark Definition, no specific libraries are used beyond built-in JavaScript functions (e.g., `Array.prototype.push()`). However, in a real-world scenario, you might use external libraries for array manipulation, such as Lodash or Ramda.

**Special JS Features/Syntax:**
None of the benchmark definitions explicitly use special JavaScript features like async/await, generators, or ES6 classes. The focus is on comparing basic array appending methods.

**Alternative Approaches:**

1. **`Array.prototype.slice()`**: Instead of using indexing (`a[j] = j;`) or updating `length`, you could try using `Array.prototype.slice()` to create a new array and then assign the values.
2. **Using `TypedArrays`**: For large arrays, you might consider using `TypedArrays` (e.g., `Int32Array`) for optimized performance and memory usage.
3. **Measuring cache performance**: To further optimize your code, you could measure the impact of caching on array appending operations.

These alternatives offer different trade-offs between performance, memory usage, and complexity, which can help you choose the best approach for specific use cases.

Latest run results:

Run details: (Test run date: 2025 years ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.146 Safari/537.36

Browser/OS: Chrome 65 on Linux

View result in a separate tab

Test name	Executions per second
index	674.9 Ops/sec
index with length	3.3 Ops/sec
push	2.2 Ops/sec

Related benchmarks:

lvng array append (version: 0)

Comparing performance of: index vs index with length vs push

Created: 6 years ago by: Guest

Jump to the latest result

index

index with length

push

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 27 days ago):