Benchmark: Date parse vs clone

Script Preparation code:

var now = new Date()
var dateStr = "2021-01-01"

Tests:

Parse
new Date(dateStr)
Clone
new Date(now)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Parse
Clone

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/109.0.0.0 Safari/537.36

Browser/OS: Chrome 109 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Parse	5565643.0 Ops/sec
Clone	7414197.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the benchmark and explore what's being tested.

The provided JSON represents a JavaScript microbenchmark, specifically comparing two approaches to parse or clone dates using the `Date` object in JavaScript.

**What is being tested?**

In the "Script Preparation Code" section of the benchmark definition, we see that a `Date` object named `now` is created and assigned the current date and time. Another string variable `dateStr` is also defined with a fixed date string "2021-01-01".

Two test cases are defined:

*   **Test Case 1: Parse**
    *   The first test case, labeled as "Parse", uses the `new Date(dateStr)` expression to parse the fixed date string.
    *   This means that when this test case is executed, it will attempt to create a new `Date` object from the provided date string.
*   **Test Case 2: Clone**
    *   The second test case, labeled as "Clone", uses the `new Date(now)` expression to clone or copy the current date and time.

**Options compared**

The two options being compared are:

*   **Parsing vs Cloning**: One option is parsing a fixed date string using the `Date` constructor (`new Date(dateStr)`), while the other option is cloning the current date and time using the same method (`new Date(now)`).
    *   **Pros of Parsing**:
        *   Faster for one-time use or if you only need to validate a specific date format.
        *   Can be beneficial when working with fixed date formats like "YYYY-MM-DD".
    *   **Cons of Parsing**: May incur additional processing overhead due to the need to parse the date string, especially for more complex formats.
*   **Cloning vs Original Date**:
    *   Pros of Cloning:
        *   Provides a snapshot of the current date and time without modifying the original value.
        *   Useful when you want to preserve the original data or ensure that the cloned value is not modified by other code.

**Other considerations**

When choosing between parsing and cloning, consider your specific use case:

*   Are you working with fixed date formats? Parsing might be more suitable.
*   Do you need to modify the original date or create a copy for further processing? Cloning would be more appropriate.
*   Is performance critical? You may want to opt for the faster option (parsing) if you only need it once.

**Library usage**

There is no explicit library mentioned in the benchmark, so we can assume that JavaScript's built-in `Date` object is being used exclusively.

**Special JS features or syntax**

The benchmark does not explicitly use any special JavaScript features or syntax. However, it is essential to note that this benchmark may be affected by JavaScript engine optimizations and caching mechanisms, which could impact the results.

**Alternatives**

If you're looking for alternatives to this specific microbenchmark, here are a few options:

*   **Benchmarking frameworks**: Consider using established benchmarking frameworks like Benchmark.js or Microbenchmark.js, which provide more advanced features and tools for writing and running benchmarks.
*   **Profiling tools**: Utilize JavaScript profiling tools like Chrome DevTools' Profiler or Node.js's built-in profiler to analyze performance bottlenecks in your application.
*   **Benchmarking libraries**: Explore dedicated benchmarking libraries like BenchmarkSuite or Jest's built-in benchmarking features, which offer more comprehensive testing capabilities.

By understanding the test case and options being compared, you can better evaluate the results of this microbenchmark and make informed decisions about performance optimization in your JavaScript applications.

Related benchmarks:

Date parse vs clone (version: 0)

Comparing performance of: Parse vs Clone

Created: one year ago by: Guest

Jump to the latest result

Parse

Clone

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):