Benchmark: shift vs pop - MeasureThat.net

Tests:

Shift
var n = 0; var t = []; while(true) { t[n] = n; n++; if(n==10) break; } n = 0; while(true){ n++; t.shift(); if(n==10) break; }
Pop
var n = 0; var t = []; while(true) { t[n] = n; n++; if(n==10) break; } n = 0; while(true){ n++; t.pop(); if(n==10) break; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Shift
Pop

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 20 days ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:150.0) Gecko/20100101 Firefox/150.0

Browser/OS: Firefox 150 on Windows

View result in a separate tab

Test name	Executions per second
Shift	3785954.0 Ops/sec
Pop	8005060.5 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**Overview**

The benchmark compares the performance of two JavaScript operations: `shift` and `pop` on an array `t`. The test creates an array with 10 elements, initializes an index variable `n` to 0, and then uses a while loop to populate the array with values from 0 to 9. After that, it increments `n` and performs either `shift` or `pop` operation on the array.

**Options Compared**

Two options are being compared:

1. **Shift**: The test pops an element from the beginning of the array using the `shift()` method.
2. **Pop**: The test removes an element from the end of the array using the `pop()` method.

**Pros and Cons of Each Approach**

**Shift:**

Pros:

* Can be faster for large arrays since it avoids creating a temporary variable.
* Often used when working with arrays that need to be sorted or have a specific order.

Cons:

* May not be as efficient on smaller arrays since the `shift()` method creates a new array and copies elements from the original array, which can lead to unnecessary memory allocation and copying.

**Pop:**

Pros:

* Can be faster for small arrays since it simply removes the last element without creating a temporary variable.
* Often used when working with arrays that need to be modified frequently, like in queue or stack implementations.

Cons:

* May not be as efficient on large arrays since the `pop()` method creates a new array and copies elements from the original array, which can lead to unnecessary memory allocation and copying.

**Other Considerations**

The test doesn't account for other factors that might affect performance, such as:

* Array size: The benchmark only tests with an array of 10 elements. Larger arrays would likely favor `shift` over `pop`.
* Browser engine: Different browser engines (e.g., V8 in Chrome, SpiderMonkey in Firefox) have different optimizations and may perform differently.
* JavaScript version: Older or newer JavaScript versions might behave differently.

**Libraries and Special JS Features**

The test doesn't use any libraries. However, if a library were used to create the array `t` or modify it after populating it with values, we would need to consider the library's impact on performance.

If special JavaScript features like async/await or generators were used in the script preparation code, they might affect the benchmark results, but there's no indication of that in the provided JSON data.

**Alternatives**

Other alternatives for this type of benchmark could include:

* Comparing the performance of `shift()` and `pop()` on a more diverse array size range (e.g., 100 elements).
* Adding other operations to the test case, like `push`, `splice`, or `slice`.
* Using a different data structure, such as a linked list or a binary search tree.
* Testing with a larger number of iterations or longer execution times.

Related benchmarks:

shift vs pop (version: 0)

Comparing performance of: Shift vs Pop

Created: 8 years ago by: Guest

Jump to the latest result

Shift

Pop

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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