Benchmark: Math.random vs i++

Script Preparation code:

let i = 0

Tests:

Math.random
Math.random()
i++
i++

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Math.random
i++

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 years ago)

User agent: Mozilla/5.0 (X11; CrOS x86_64 15054.98.0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/106.0.0.0 Safari/537.36

Browser/OS: Chrome 106 on Chrome OS 15054.98.0

View result in a separate tab

Test name	Executions per second
Math.random	2850475.8 Ops/sec
i++	206079792.0 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):

LLMs can make mistakes. Check important info.

Let's dive into explaining what's being tested in the provided benchmark.

**Benchmark Overview**

The benchmark is designed to compare two approaches: using `Math.random()` and incrementing a variable (`i++`). This comparison aims to determine which method is faster, as measured by the number of executions per second.

**Options Compared**

There are two main options being compared:

1. **`Math.random()`**: This function generates a random number between 0 (inclusive) and 1 (exclusive). It's a widely used method for generating pseudo-random numbers in JavaScript.
2. **`i++`**: This is an increment operator that increments the value of `i` by 1. In this context, it's being used as a simple loop counter.

**Pros and Cons**

* **`Math.random()`**:
	+ Pros: widely supported, easy to use, and suitable for generating random numbers.
	+ Cons: can be slower than incrementing a variable due to the overhead of generating a random number.
* **`i++`**:
	+ Pros: very fast, as it only increments a simple variable.
	+ Cons: requires manual management of the loop counter (e.g., initializing and incrementing `i`) and may not be suitable for complex loops.

**Library and Special JS Feature**

In this benchmark, none of the test cases use any external libraries. The only special feature used is **increment operator (`++`)**, which increments a variable by 1. This is a standard JavaScript syntax that's widely supported across most implementations.

**Other Considerations**

When measuring performance in a benchmark like this, it's essential to consider factors such as:

* Cache performance: How does the use of `Math.random()` vs. incrementing a variable affect cache performance?
* Branch prediction: Does the choice between `Math.random()` and incrementing a variable impact branch prediction?
* Loop optimization: Are there any loop optimizations or optimizations available in modern JavaScript engines that might favor one approach over the other?

**Alternatives**

If you're interested in exploring alternative approaches, here are some ideas:

* **Use a faster random number generator**: Some modern JavaScript engines have optimized random number generators, such as the `crypto` module.
* **Experiment with loop unrolling or optimization**: Investigate if there's any potential for optimizing loops to improve performance.
* **Compare with other incrementing methods**: Try using different increment operators (e.g., `++i`, `i += 1`) and see how they compare to `Math.random()`.

Related benchmarks:

Math.random vs i++ (version: 0)

Comparing performance of: Math.random vs i++

Created: 3 years ago by: Guest

Jump to the latest result

Math.random

i++

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 6 months ago):