Benchmark: update Element in a array test _tarcisio.magno

Script Preparation code:

var oldData = Array.from({
    length: 10000000
}, (_, index) => ({
    id: index + 1,
    name: `name_${index+1}`,
    version: "0",
    active: true
}));

var row = {
    id: 1
}

function sliceMethod(oldData, row) {
    const index = oldData.findIndex(
        item => item.id === row.id
    );
    return {
        queues: {
            data: [
                ...oldData.slice(0, index),
                {
                    ...oldData[index],
                    active: true,
                    version: String(
                        +oldData[index].version + 1
                    )
                },
                ...oldData.slice(index + 1)
            ]
        }
    };
}

function mapMethod(oldData, row) {
    const data = oldData.map(item => {
        if (item.id !== row.id) return item
        return {
            ...item,
            active: true,
            version: String(+item.version + 1)
        };
    })
    return {
        queues: {
            data
        }
    };
}

Tests:

Map Method
mapMethod(oldData, row);
Slice Method
sliceMethod(oldData,row);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Map Method
Slice Method

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

I'll break down the benchmark and explain what's being tested, compared options, pros and cons, and other considerations.

**Benchmark Definition:**

The benchmark is designed to test the performance of two different methods for updating an element in an array: `sliceMethod` and `mapMethod`. The input data is a large array (`oldData`) with 10 million elements, each containing an `id`, `name`, `version`, and `active` property.

**Script Preparation Code:**

The script preparation code generates the `oldData` array using JavaScript's Array.from() method. It also defines two functions: `sliceMethod` and `mapMethod`. These functions are the focus of the benchmark.

*   `sliceMethod`: This function takes two arguments, `oldData` and `row`, where `row` is an object with an `id` property matching one in `oldData`. The function returns a new object with the modified array, using the `slice()` method to split the original array into two parts at the index of the matched row. It then updates the version number for the matched row and combines the two parts back together.
*   `mapMethod`: This function also takes two arguments, `oldData` and `row`, with the same logic as `sliceMethod`. However, instead of using the `slice()` method, it uses the `map()` method to create a new array containing the modified rows. The updated version numbers are applied directly to the original elements in the mapped array.

**Comparison:**

The two methods being compared are:

1.  `Slice Method` (`sliceMethod`): This approach uses the `slice()` method to manipulate the array, which can be slower because it creates new arrays and copies data.
2.  `Map Method` (`mapMethod`): This approach uses the `map()` method to create a new array with modified elements. It's often faster than using `slice()` because it avoids creating intermediate arrays.

**Pros and Cons:**

*   **Slice Method (sliceMethod)**:
    *   Pros:
        *   Can be more predictable in terms of memory usage.
        *   Might be more suitable for certain use cases where exact control over array manipulation is required.
    *   Cons:
        *   Can be slower due to the creation of intermediate arrays and copying data.
*   **Map Method (mapMethod)**:
    *   Pros:
        *   Generally faster because it avoids creating intermediate arrays and uses less memory.
        *   More suitable for large datasets where performance is critical.
    *   Cons:
        *   Can be more complex to understand due to the use of callback functions.

**Library:**

There isn't a specific library mentioned in the benchmark definition. However, JavaScript's built-in `Array.prototype.slice()` and `Array.prototype.map()` methods are being used.

**Special JS Feature or Syntax:**

No special JavaScript features or syntax are explicitly being tested in this benchmark. The focus is on comparing the performance of two different array manipulation approaches.

**Alternatives:**

Other alternatives for updating an element in an array could include:

*   Using `forEach()` with a callback function to iterate over the elements and update them.
*   Utilizing libraries like Lodash or Underscore.js, which provide methods like `map()`, `filter()`, and `findIndex()`.

Keep in mind that the choice of approach depends on the specific requirements of your application, such as performance, readability, and memory usage.

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/116.0.0.0 Safari/537.36

Browser/OS: Chrome 116 on Windows

View result in a separate tab

Test name	Executions per second
Map Method	3.4 Ops/sec
Slice Method	1.4 Ops/sec

Related benchmarks:

update Element in a array test _tarcisio.magno (version: 1)

Comparing performance of: Map Method vs Slice Method

Created: one year ago by: Registered User

Jump to the latest result

Map Method

Slice Method

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):