Benchmark: set vs array iteration 100kf

Script Preparation code:

var a = new Array(100000);
for (let i=0; i<100000; i++) {
	a[i] = i;
}
var b = new Set(a)

Tests:

array
for (const x of a) {}
set
for (const x of b) {}

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
array
set

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark definition and test cases.

**Benchmark Definition**

The benchmark is designed to compare the performance of iterating over an array versus a Set data structure in JavaScript. The script preparation code creates two large arrays and sets, each with 100,000 elements, and then assigns each element to a unique index in the array. A for...of loop is used to iterate over both the array and set.

**Options Compared**

Two options are compared:

1. **Array Iteration**: This involves using the traditional `for` loop with an index variable (`i`) to iterate over the elements of the array.
2. **Set Iteration**: This involves using the `for...of` loop with a const variable (`x`) to iterate over the elements of the Set data structure.

**Pros and Cons**

* **Array Iteration**:
	+ Pros: Generally, arrays are faster and more efficient than Sets for iteration due to the caching and indexing benefits provided by JavaScript engines.
	+ Cons: Arrays require manual indexing, which can lead to slower performance if not optimized correctly.
* **Set Iteration**:
	+ Pros: Set iteration provides a more concise and expressive way of iterating over data, making it easier to write code that is readable and maintainable. Sets also provide additional benefits like fast membership testing and automatic removal of duplicates.
	+ Cons: Set iteration may be slower than array iteration due to the overhead of implementing the Set data structure and its associated algorithms.

**Libraries Used**

None

**Special JS Features or Syntax**

* **for...of loops**: Introduced in ECMAScript 2015, for...of loops provide a more concise way of iterating over iterable objects like arrays and sets.
* **Set data structure**: Introduced in ECMAScript 1999, Set provides an efficient way to store unique values.

**Other Considerations**

When writing benchmarks, it's essential to consider factors like:

* **Data size**: The larger the dataset, the more significant the performance difference between array and set iteration may be.
* **Engine optimizations**: Different JavaScript engines (e.g., V8 in Chrome) may have varying levels of optimization for array and set iteration.
* **Hardware and software overheads**: Factors like CPU frequency, memory access patterns, and operating system overhead can impact benchmark results.

**Alternatives**

Other alternatives for iterating over data structures include:

* Using `Array.prototype.forEach()` or `Set.prototype.forEach()`, which are more concise but may be slower than traditional loops.
* Utilizing third-party libraries like Lodash or Ramda for functional programming and array/set operations.
* Implementing custom iterators or iterator factories to create optimized iteration logic.

When interpreting benchmark results, it's crucial to consider the specific test case, data size, engine optimizations, and hardware/software overheads that may impact performance.

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.36

Browser/OS: Chrome 119 on Windows

View result in a separate tab

Test name	Executions per second
array	23987.3 Ops/sec
set	6521.1 Ops/sec

Related benchmarks:

set vs array iteration 100kf (version: 0)

Comparing performance of: array vs set

Created: one year ago by: Guest

Jump to the latest result

array

set

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):