Benchmark: Anonymous Function in Loop

Script Preparation code:

var x = 0;

function doSomething(x) {
  return x++;
}

Tests:

A
for(var i=0; i < 10; i++) { (function(someValue) { return x++; })(i); }
B
for(var i=0; i < 10; i++) { doSomething(i); }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
A
B

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/109.0.0.0 Safari/537.36

Browser/OS: Chrome 109 on Linux

View result in a separate tab

Test name	Executions per second
A	880932.7 Ops/sec
B	2148076.8 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark definition and test cases to understand what's being tested.

**Benchmark Definition**

The benchmark is comparing two approaches:

1. **Closure creation in a loop**: This involves creating a new function inside a loop that captures the `i` variable from the outer scope, creates a closure by returning `x++`, and increments `x`.
2. **Function call with parameter passing**: This approach simply calls the `doSomething` function with the current value of `i` as an argument.

**Options Compared**

The options being compared are:

* Creating a new function inside a loop (closure creation)
* Passing the parameter to the existing function (`doSomething`) without creating a new function

**Pros and Cons of each approach:**

1. **Closure Creation**:
	* Pros:
		+ Can be faster because it avoids the overhead of passing an argument to `doSomething`.
		+ May exhibit different performance characteristics due to the closure's capture behavior.
	* Cons:
		+ Creates a new function on each iteration, which can lead to increased memory allocation and garbage collection.
		+ The function captures the outer scope's variable `x`, which may have unexpected side effects if `x` is modified elsewhere in the program.
2. **Function Call with Parameter Passing**:
	* Pros:
		+ No additional memory allocation or garbage collection overhead.
		+ Easier to understand and maintain, as the intent of passing an argument is clear.
	* Cons:
		+ May be slower due to the overhead of calling `doSomething` and passing the argument.

**Library/Function Usage**

The benchmark uses a custom function called `doSomething`, which takes a single parameter `x`. The purpose of this function is not explicitly stated, but based on its implementation, it appears to increment the value of `x` by 1 and return it.

**Special JS Feature/Syntax**

There are no explicit mentions of special JavaScript features or syntax in the benchmark definition. However, it's worth noting that the use of arrow functions (`(function(someValue) { ... })(i);`) is a modern feature introduced in ECMAScript 2015 (ES6). This may be relevant if the benchmark is intended to demonstrate performance characteristics for this specific syntax.

**Other Alternatives**

In addition to the two approaches being compared, other alternatives might include:

* Using an array or similar data structure to store and reuse the closures created in each iteration.
* Implementing a custom caching mechanism to avoid creating multiple instances of `doSomething` on each iteration.
* Using a different JavaScript engine or virtual machine (VM) to execute the benchmark.

Keep in mind that the specific alternatives will depend on the goals and requirements of the benchmark.

Related benchmarks:

Anonymous Function in Loop (version: 0)

Comparing performance of: A vs B

Created: 7 years ago by: Guest

Jump to the latest result

A

B

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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