Benchmark: frozen and normal object

Script Preparation code:

const baseObj = Object.fromEntries(Array.from({ length: 1000 }, () => Math.random().toString(16).slice(2)).map((elem, i) => [i.toString(), elem]))

var obj = Object.assign({}, baseObj);
var frozen = Object.freeze(Object.assign({}, baseObj));

function getElem(obbj, elem) {
  return obbj[elem];
};

Tests:

frozen
for (let i = 0; i < 100000; i++) { getElem(frozen, (i % 10).toString()) }
normal
for (let i = 0; i < 100000; i++) { getElem(obj, (i % 10).toString()) }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
frozen
normal

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

I'll break down the provided JSON benchmark definition and test cases to explain what's being tested, compared, and their pros and cons.

**Benchmark Definition**

The provided JSON represents a JavaScript microbenchmark that tests the performance of two approaches: freezing an object (frozen) and not freezing an object (normal).

**Script Preparation Code**

This code generates two objects:
```javascript
const baseObj = Object.fromEntries(Array.from({ length: 1000 }, () => Math.random().toString(16).slice(2)).map((elem, i) => [i.toString(), elem]));
var obj = Object.assign({}, baseObj);
var frozen = Object.freeze(Object.assign({}, baseObj));
```
Here's what's happening:

1. `Object.fromEntries` creates an object from an array of key-value pairs.
2. `Array.from({ length: 1000 }, () => Math.random().toString(16).slice(2))` generates an array of 1000 random strings (32-character hex codes).
3. The `map()` method creates a new array with the same number of elements as the original, where each element is a key-value pair (`[i.toString(), elem]`).
4. `Object.assign({}, baseObj)` creates a shallow copy of `baseObj`.
5. `Object.freeze(Object.assign({}, baseObj))` freezes the copied object, making it immutable.

**Html Preparation Code**

This field is empty in the provided JSON, which means there's no HTML preparation code for this benchmark.

**Individual Test Cases**

There are two test cases:

1. **Frozen**
```javascript
for (let i = 0; i < 100000; i++) { getElem(frozen, (i % 10).toString()) }
```
This test case uses a simple `for` loop to iterate 100,000 times and call the `getElem()` function on the frozen object with a random key as an argument.

2. **Normal**
```javascript
for (let i = 0; i < 100000; i++) { getElem(obj, (i % 10).toString()) }
```
This test case is similar to the frozen one but uses the non-frozen object (`obj`) instead of the frozen one.

**Pros and Cons**

1. **Frozen**: Freezing an object makes it immutable, which can prevent certain types of mutations (e.g., assigning a new value to a property). However, this comes at a performance cost, as JavaScript needs to create a new object when you try to modify a frozen property.
	* Pros: Prevents accidental mutations, provides thread-safety for concurrent access.
	* Cons: Slower due to object creation and property lookup.
2. **Normal**: Not freezing an object means that it can be modified freely, but this comes with the risk of unintended side effects or data corruption.
	* Pros: Faster performance due to fewer object creations and less expensive property lookups.
	* Cons: Risk of accidental mutations, potential thread safety issues.

**Library**

There's no specific library mentioned in the provided JSON. However, `Object.fromEntries` is a modern JavaScript feature introduced in ECMAScript 2015 (ES6), which allows creating objects from arrays of key-value pairs. If you need to support older browsers or environments that don't have this feature, you might need to use an alternative library or polyfill.

**Special JS Feature/Syntax**

There's no special JavaScript feature or syntax mentioned in the provided JSON. However, if you're using a modern browser or environment that supports ES6 features, you should be aware of the potential performance implications of using `Object.fromEntries` and other modern features like arrow functions (`=>`) and template literals (`\r\n`).

**Other Alternatives**

If you need to create benchmarks for similar use cases, consider exploring alternative approaches:

1. **Use a different data structure**: Instead of objects, you could use arrays or other data structures that might be more suitable for your specific use case.
2. **Experiment with different freezing strategies**: Depending on your requirements, you might want to explore alternative freezing techniques, such as using `Object.freeze()` only for certain properties or using a custom freezing function.
3. **Investigate parallel processing**: If performance is critical, consider using parallel processing techniques, like web workers or async/await, to run multiple benchmarks concurrently.
4. **Explore other benchmarking frameworks**: Depending on your needs and the specific use case, you might want to explore alternative benchmarking frameworks that offer more advanced features or better support for certain platforms or environments.

Latest run results:

Run details: (Test run date: 5 months ago)

User agent: Mozilla/5.0 (Linux; Android 10; K) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Mobile Safari/537.36

Browser/OS: Chrome Mobile 125 on Android

View result in a separate tab

Test name	Executions per second
frozen	80.9 Ops/sec
normal	79.4 Ops/sec

Related benchmarks:

frozen and normal object (version: 0)

Comparing performance of: frozen vs normal

Created: 5 months ago by: Guest

Jump to the latest result

frozen

normal

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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