Benchmark: Map generator test

Script Preparation code:

function* mapGen(iterable, callback) {
  //iterable[Symbol.iterator]();

  for (const item of iterable) {
    yield callback(item);
  }
}

var loops = 1000;
var items = Array(1000).fill(0);

Tests:

Map
let a2 = items.map((i) => i.toString()); let b2 = a2.map((i) => parseInt(i)); for (let i = 0; i < loops; ++i) { b2 = b2.map((i) => i); }
Gen Map
let a1 = mapGen(items, (i) => i.toString()); let b1 = mapGen(a1, (i) => parseInt(i)); for (let i = 0; i < loops; ++i) { b1 = mapGen(b1, (i) => i); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Map
Gen Map

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 benchmark JSON and individual test cases to understand what's being tested.

**Benchmark Definition**

The benchmark definition is a JavaScript function that creates a generator (`mapGen`) which takes an iterable and a callback function as arguments. The `mapGen` function yields the result of applying the callback function to each item in the iterable.

The script preparation code includes:

* A loop variable `loops` set to 1000, which controls the number of iterations.
* An array `items` filled with 1000 zeros.

**Individual Test Cases**

There are two test cases:

1. **"Map"`**
This test case is identical to a built-in JavaScript function that maps an array to a new array by applying a callback function to each element. The benchmark definition code is:
```javascript
let a2 = items.map((i) => i.toString());
let b2 = a2.map((i) => parseInt(i));

for (let i = 0; i < loops; ++i) {
  b2 = b2.map((i) => i);
}
```
This test case compares the performance of using the built-in `map()` function versus calling it manually.

Pros and Cons:

* **Built-in `map()`**: Pros:
	+ Optimized for performance by the JavaScript engine.
	+ Typically faster than manual implementation.
	+ Easier to read and maintain.
* **Manual implementation**: Pros:
	+ Can be optimized for specific use cases or hardware.
	+ Can be used to bypass built-in function optimizations.

2. **"Gen Map"`**
This test case uses the `mapGen` generator created in the benchmark definition to map an array to a new array by applying a callback function to each element.

The benchmark definition code is:
```javascript
let a1 = mapGen(items, (i) => i.toString());
let b1 = mapGen(a1, (i) => parseInt(i));

for (let i = 0; i < loops; ++i) {
  b1 = mapGen(b1, (i) => i);
}
```
This test case compares the performance of using a custom generator versus the built-in `map()` function.

Pros and Cons:

* **Custom generator**: Pros:
	+ Can be optimized for specific use cases or hardware.
	+ Can provide more control over the iteration process.
* **Built-in `map()`**: Pros:
	+ Optimized for performance by the JavaScript engine.
	+ Typically faster than manual implementation.

**Other Considerations**

The benchmark results show that the custom generator (`Gen Map`) is significantly slower than the built-in `map()` function on this specific test case. This might be due to various factors, such as:

* Overhead of creating and managing a custom iterator
* Complexity of the iteration process

However, there might be scenarios where the custom generator provides benefits, such as:

* Better control over the iteration process
* Optimization for specific use cases or hardware

**Alternatives**

If you want to optimize the performance of your JavaScript code, consider using:

1. **Native WebAssembly (WASM) modules**: Can provide significant performance improvements compared to JavaScript.
2. **Just-In-Time (JIT) compilation**: Some JavaScript engines, like SpiderMonkey, offer JIT compilation for specific code paths.
3. **Profiling and optimization tools**: Use tools like Chrome DevTools or Node.js Inspector to identify performance bottlenecks and optimize your code.

Remember that the choice of implementation depends on the specific use case, performance requirements, and personal preference.

Related benchmarks:

Map generator test (version: 0)

Comparing performance of: Map vs Gen Map

Created: 4 years ago by: Guest

Jump to the latest result

Map

Gen Map

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):