Benchmark: findIndex update vs for loop update edited 1

Script Preparation code:

var arr = new Array(2000000);
arr.fill({
    id: 0
});
arr = arr.map((el, idx) => el.id = idx);

var findItemIndex = (idToFind, list) => {
    var index = -1
    for (var i = 0; i < list.length; i++) {
        if (list[i].id === idToFind) {
            index = i;
            break;
        }
    }

    return index;
}
var itemsToUpdate = [{
    id: 100,
    updates: {
        name: "111"
    }
}, {
    id: 200,
    updates: {
        name: "111"
    }
}, {

    id: 400,
    updates: {
        name: "111"
    }

}, {
    id: 600,
    updates: {
        name: "111"
    }

}, {
    id: 800,
    updates: {
        name: "111"
    }

}]

Tests:

update via findIndex
itemsToUpdate.forEach((t) => { const storedIndex = arr.findIndex((tD) => { return tD.id === t.id }) if(storedIndex >= 0){ arr[storedIndex] = { ...arr[storedIndex], ...t.updates } } })
for loop update
itemsToUpdate.forEach((t) => { const storedIndex = findItemIndex(t.id, arr) if(storedIndex >= 0){ arr[storedIndex] = { ...arr[storedIndex], ...t.updates } } })

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
update via findIndex
for loop update

Fastest: N/A

Slowest: N/A

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/131.0.0.0 Safari/537.36

Browser/OS: Chrome 131 on Windows

View result in a separate tab

Test name	Executions per second
update via findIndex	21.2 Ops/sec
for loop update	167.6 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 and explain what is being tested, the options compared, their pros and cons, and other considerations.

**Benchmark Definition**

The benchmark definition represents two different approaches to update elements in an array:

1. **For loop update**: The first approach uses a for loop to iterate over the `itemsToUpdate` array and updates each element in the `arr` array using the `findIndex` method.
2. **Update via findIndex**: The second approach uses the `findItemIndex` function to find the index of each element in the `arr` array and then updates the corresponding element using the `findIndex` method.

**Options Compared**

The two options being compared are:

* For loop update
* Update via findIndex

**Pros and Cons**

1. **For loop update**:
	* Pros: Generally faster and more efficient, as it avoids the overhead of the `findItemIndex` function.
	* Cons: Can be slower for large arrays, as it requires iterating over each element individually.
2. **Update via findIndex**:
	* Pros: More concise and elegant, as it uses a single function to perform both finding and updating operations.
	* Cons: May be slower due to the overhead of the `findItemIndex` function.

**Other Considerations**

* The benchmark is using a large array of 2 million elements for testing.
* Both approaches assume that the element being updated has an `id` property that can be used for lookup.
* The `itemsToUpdate` array contains five elements with identical `updates` objects, which may affect the performance results.

**Library and Special JS Feature**

The benchmark is using the following library:

* None explicitly mentioned, but it's likely that the JavaScript engine being tested (e.g., V8 in Chrome) is using its built-in implementation of the `findIndex` method.

There are no special JavaScript features or syntax used in this benchmark beyond what's standard for JavaScript.

**Alternatives**

Other alternatives for updating elements in an array include:

* Using `Array.prototype.map()` with a callback function, which can be more concise but may have performance implications.
* Using `Array.prototype.forEach()` with a callback function, which can provide better error handling and debugging capabilities.
* Implementing custom iteration logic using `for...of` loops or recursive functions.

However, the for loop update and update via findIndex approaches are likely to be among the most common and efficient methods used in practice.

Related benchmarks:

findIndex update vs for loop update edited 1 (version: 2)

Comparing performance of: update via findIndex vs for loop update

Created: 3 years ago by: Registered User

Jump to the latest result

update via findIndex

for loop update

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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