Benchmark: create_UUID - MeasureThat.net

Script Preparation code:

function create_UUID1(a){return a?(a^Math.random()*16>>a/4).toString(16):([1e7]+-1e3+-4e3+-8e3+-1e11).replace(/[018]/g,create_UUID1)}
function create_UUID2() {
  var dt = new Date().getTime();
  var uuid = 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function (c) {
    var r = (dt + Math.random() * 16) % 16 | 0;
    dt = Math.floor(dt / 16);
    return (c == 'x' ? r : (r & 0x3 | 0x8)).toString(16);
  });
  return uuid;
}

Tests:

create_UUID1
create_UUID1()
create_UUID2
create_UUID2()

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
create_UUID1
create_UUID2

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 dive into the world of JavaScript microbenchmarks!

The provided JSON represents a benchmark for measuring the performance of creating UUIDs (Universally Unique Identifiers) in JavaScript. The test consists of two individual test cases: `create_UUID1` and `create_UUID2`.

**What are UUIDs?**

UUIDs are 128-bit numbers used to identify information objects uniquely. They have several benefits, including:

* Uniqueness
* High entropy (good distribution)
* Low collision rate

**Script Preparation Code**

The script preparation code is the JavaScript function that generates a UUID. There are two functions in this benchmark:

1. `create_UUID1(a)`:
This function uses bitwise operations and Math.random() to generate a UUID. It's an example of a simple, self-referential algorithm. The pros of this approach include:

* Simplicity
* Fast execution

However, the cons are:

* Low entropy due to the use of Math.random()
* Potential issues with seed value propagation (see below)

2. `create_UUID2()`:
This function uses the Date object and a template string to generate a UUID. It's an example of a more complex algorithm that generates a random UUID based on the current timestamp.

Pros:

* High entropy due to the use of Date object and random number generation
* Robust against seed value propagation issues

Cons:

* More complex implementation
* Potential performance overhead due to the use of template strings and Date object

**Library:**

There is no explicit library used in these functions, but we can assume that `Math.random()` is a built-in function.

**Special JS Feature/Syntax:**

`create_UUID1(a)` uses a self-referential algorithm, which might be considered an advanced JavaScript concept. However, this example is more of a demonstration of bitwise operations and Math.random() usage rather than showcasing a specific feature or syntax.

**Other Considerations:**

When creating UUIDs, it's essential to consider the following:

* Collision rate: The likelihood of generating duplicate UUIDs.
* Entropy: The amount of randomness in the generated UUIDs.
* Seed value propagation: The impact of seed values on subsequent generations.

**Alternatives:**

If you need a high-quality UUID library for production use, there are several options available:

* `uuid.js`: A lightweight JavaScript library for generating UUIDs.
* `node-uuid`: A Node.js library for generating UUIDs.
* `crypto`: Many browsers have a built-in `crypto` module that provides functions for generating UUIDs.

For benchmarking purposes, you can also use libraries like `benchmark` or `micro-benchmark`, which provide a simple way to measure the performance of JavaScript code.

In conclusion, this benchmark highlights the importance of considering entropy and seed value propagation when generating UUIDs. The two test cases demonstrate different approaches to creating UUIDs: one simple and self-referential, and the other more complex but robust.

Related benchmarks:

create_UUID (version: 0)

Comparing performance of: create_UUID1 vs create_UUID2

Created: 7 years ago by: Guest

Jump to the latest result

create_UUID1

create_UUID2

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):