Benchmark: arr unshift vs push

Tests:

unshift
const arr = []; for (let i = 0; i < 10; i++){ arr.unshift('string'); }
push
const arr = []; for (let i = 0; i < 10; i++){ arr.push('string'); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
unshift
push

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/605.1.15 (KHTML, like Gecko) Version/16.4 Safari/605.1.15

Browser/OS: Safari 16 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
unshift	4381512.0 Ops/sec
push	28047522.0 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Benchmark Overview**

The benchmark is comparing the performance of two array operations: `unshift` and `push`. Both tests create an empty array, then populate it with 10 string elements using a `for` loop. The main difference between the two tests is where the string elements are appended to the array: either at the beginning (`unshift`) or end (`push`).

**Options Compared**

There are only two options being compared:

1. `unshift`: Appends strings to the beginning of the array.
2. `push`: Appends strings to the end of the array.

**Pros and Cons**

* **`unshift`**:
	+ Pros: Can be faster when dealing with large arrays, as it avoids the overhead of shifting existing elements to make space for new ones.
	+ Cons: Requires the entire array to be populated before adding elements, which can lead to slower performance if the array grows dynamically.
* **`push`**:
	+ Pros: More efficient when dealing with small or dynamic arrays, as it only requires appending a single element to the end of the array.
	+ Cons: Can be slower for large arrays due to the need to shift existing elements.

**Library Usage**

The benchmark uses no external libraries. It's likely that the script preparation code is using built-in JavaScript features and standard library functions (e.g., `Array.prototype.unshift` and `Array.prototype.push`) to create the test data and execute the benchmarks.

**Special JS Features or Syntax**

There are no special JS features or syntax mentioned in the benchmark definition or individual test cases. The focus is solely on comparing the performance of two basic array operations: `unshift` and `push`.

**Other Alternatives**

If you're interested in exploring alternative approaches, here are a few options:

1. **Slicing vs. Splice**: Instead of using `unshift` or `push`, consider testing `Array.prototype.slice()` or `Array.prototype.splice()`. These methods can provide different performance characteristics depending on the specific use case.
2. **Other array operations**: Explore other array operations, such as `concat()`, `forEach()`, or `map()`, to see how they compare in terms of performance.
3. **Multi-threading or parallel execution**: If you have a multi-core processor, consider testing if running multiple threads or executing benchmarks in parallel can improve performance.

Keep in mind that these alternatives may require modifications to the benchmark definition and script preparation code to accurately represent the desired use cases.

Related benchmarks:

arr unshift vs push (version: 5)

Comparing performance of: unshift vs push

Created: one year ago by: Registered User

Jump to the latest result

unshift

push

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):