Benchmark: pushing large array vs destructuring

Tests:

destructuring
let firstLargeArray = Array.from({length: 100000}, (_,i) => i+1) const secondLargeArray = Array.from({length: 100000}, (_,i) => i+1) firstLargeArray = [...firstLargeArray, ...secondLargeArray]
pushing
let firstLargeArray = Array.from({length: 100000}, (_,i) => i+1) const secondLargeArray = Array.from({length: 100000}, (_,i) => i+1) firstLargeArray.push(...secondLargeArray)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
destructuring
pushing

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/134.0.0.0 Safari/537.36 Edg/134.0.0.0

Browser/OS: Chrome 134 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
destructuring	219.1 Ops/sec
pushing	208.7 Ops/sec

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

LLMs can make mistakes. Check important info.

I'd be happy to explain what's being tested in this benchmark.

**Benchmark Overview**

The benchmark compares two approaches for concatenating large arrays: destructuring and pushing.

**Destructuring Approach**

In the "destructuring" test case, an array is created using `Array.from()` with a generator function that generates numbers from 1 to 100000. Two identical large arrays are created this way. Then, one of the arrays is assigned the value of the other array using destructuring syntax (`[...firstLargeArray, ...secondLargeArray]`). The resulting array is then stored in a variable.

**Pushing Approach**

In the "pushing" test case, an array is created similarly to the destructuring approach. Two identical large arrays are created this way. Then, one of the arrays is pushed the other array using the `push()` method (`firstLargeArray.push(...secondLargeArray)`). The resulting array is then stored in a variable.

**Comparison**

The benchmark measures the performance difference between these two approaches.

**Pros and Cons of Each Approach:**

* **Destructuring Approach**
	+ Pros:
		- More concise and expressive syntax.
		- Can be more efficient because it avoids creating a new array with `Array.prototype.concat()`.
	+ Cons:
		- May have higher overhead due to the creation of a new scope and function call.
* **Pushing Approach**
	+ Pros:
		- Typically has lower overhead compared to destructuring, as it uses an existing method (`push()`).
	+ Cons:
		- Requires creating a new array with `Array.prototype.concat()`, which can be expensive for large arrays.

**Library and Special JavaScript Features**

No special libraries or features are used in this benchmark. However, the use of generator functions is notable. Generator functions allow defining iterators using the `yield` keyword, which can improve performance by avoiding the creation of intermediate values.

**Other Considerations**

This benchmark focuses on measuring the performance difference between two specific array concatenation approaches. Other factors that might affect performance include:

* Browser and device-specific optimizations
* Memory allocation and deallocation overhead
* Garbage collection and memory management

It's worth noting that this benchmark is likely to focus on CPU-bound workloads, such as those involving large arrays and array operations.

**Alternative Benchmarks**

Other alternatives for measuring the performance of array concatenation approaches might include:

* Measuring the time it takes to concatenate two large arrays using `Array.prototype.concat()`
* Comparing the performance of different array allocation strategies (e.g., creating an array with a pre-allocated size vs. dynamically allocating memory)
* Benchmarking other array manipulation methods, such as using `splice()` or `reduce()`

Keep in mind that these alternative benchmarks would likely require significant changes to the benchmarking script and may not be directly comparable to this benchmark.

Related benchmarks:

pushing large array vs destructuring (version: 0)

Comparing performance of: destructuring vs pushing

Created: 2 years ago by: Guest

Jump to the latest result

destructuring

pushing

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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