Benchmark: check index access speed

Script Preparation code:

var arr = [];
var i = 0;

while (i <= 1E5) arr[i] = i++;

var obj = {};
var j = 0;
while (j <= 1E5) obj[String(j)] = j++;

Tests:

findIndex
const item = arr.findIndex(i => i === 1E5);
index access
const b = obj[String(1E5)];

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
findIndex
index access

Fastest: N/A

Slowest: N/A

Latest run results:

No previous run results

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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 definition and test cases to understand what is being tested.

**Benchmark Definition**

The benchmark definition consists of two parts:

1. **Script Preparation Code**: This code generates an array `arr` of size 100,000 and an object `obj` of size 100,000. The arrays are populated with incremental values starting from 0.
2. **Html Preparation Code**: This field is empty, which means the benchmark doesn't require any HTML setup.

**Test Cases**

There are two test cases:

1. **findIndex**
	* Benchmark Definition: `const item = arr.findIndex(i => i === 1E5);`
	* Purpose: Test the performance of finding a specific element in the array `arr`.
2. **index access**
	* Benchmark Definition: `const b = obj[String(1E5)];`
	* Purpose: Test the performance of accessing an index in the object `obj`.

**What is being tested?**

The benchmark is testing the speed of:

* Finding a specific element in an array using `Array.prototype.findIndex()`.
* Accessing a specific key in an object using bracket notation (e.g., `obj[String(1E5)]`).

**Options Compared**

In the test cases, two approaches are compared:

1. **findIndex**: uses `Array.prototype.findIndex()` to find the index of the element in the array.
2. **index access**: uses bracket notation to directly access the key-value pair in the object.

**Pros and Cons**

Here's a brief summary of the pros and cons of each approach:

**findIndex**

Pros:

* Efficient for large arrays ( O(n) average time complexity)
* Allows early exit when the element is not found

Cons:

* May incur additional overhead due to function call and iteration
* Can be slower than direct indexing if the array is small or sparse

**index access**

Pros:

* Directly accesses the key-value pair, potentially faster for small arrays or sparse objects
* May have lower memory usage due to fewer allocations

Cons:

* May fail if the object does not exist or the key is not present (throws an error)
* Can be slower than `findIndex` for large datasets

**Library and Syntax**

The benchmark uses the following libraries and syntax:

* No external libraries are explicitly mentioned.
* The `String()` function is used to convert numbers to strings, which allows using bracket notation on objects.

**Special JS Features or Syntax**

There's no mention of any special JavaScript features or syntax in the provided benchmark definition. However, the use of `1E5` as a literal value suggests that the benchmark is designed to work with a specific version of JavaScript that supports this notation (likely ECMAScript 2015 or later).

**Alternatives**

Other alternatives for testing array and object lookup performance might include:

* Using `Array.prototype.indexOf()` instead of `findIndex`
* Using `Object.keys()`, `Object.values()`, or other iteration methods to access object properties
* Using a different data structure, such as a Map or Set, to store the data

Keep in mind that the choice of alternative will depend on the specific requirements and constraints of your benchmarking project.

Related benchmarks:

check index access speed (version: 0)

speed

Comparing performance of: findIndex vs index access

Created: 2 years ago by: Guest

Jump to the latest result

findIndex

index access

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

No previous run results

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