Benchmark: Comparing date allocation

Tests:

Date from string
const dateString = "2024-05-31T09:13:43.095Z"; if (/^\d+-\d+-\d+T\d+:\d+:\d+(\.\d+)?$/.test(dateString)) { dateString += 'Z'; } const result = Date.parse(dateString); isNaN(result) ? null : (result / 1000.0);
Just assigning string
const dateString = "2024-05-31T09:13:43.095Z";

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Date from string
Just assigning string

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/605.1.15 (KHTML, like Gecko) Version/17.3.1 Safari/605.1.15

Browser/OS: Safari 17 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
Date from string	9243965.0 Ops/sec
Just assigning string	502514752.0 Ops/sec

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

LLMs can make mistakes. Check important info.

I'd be happy to help you understand the benchmark.

**What is being tested?**

The provided JSON represents a JavaScript microbenchmarking test case on MeasureThat.net. The test aims to compare two approaches:

1.  **Direct Date.parse**: This approach involves directly parsing a date string using `Date.parse()` function.
2.  **Deferred Date Creation**: This approach involves delaying the creation of a date object until it is actually needed.

The benchmark compares the performance of these two approaches on converting a specific date string.

**Options being compared:**

The test case has two options:

1.  **Just assigning string**: In this approach, the date string is assigned to a variable without any processing.
2.  **Date from string**: In this approach, the date string is processed by first checking if it matches a specific format and then parsing it using `Date.parse()` function.

**Pros and Cons of each approach:**

*   **Direct Date.parse**:
    *   Pros:
        *   Simple and straightforward.
        *   Does not require additional processing or checks.
    *   Cons:
        *   May be slower due to the overhead of parsing a potentially invalid date string.
        *   Requires `Date.parse()` function, which may not always return a valid result.

*   **Deferred Date Creation**:
    *   Pros:
        *   Can improve performance by deferring the creation of a date object until it is actually needed.
    *   Cons:
        *   Requires additional processing and checks to determine if the string represents a valid date.
        *   May add complexity to the code.

**Library:**

There is no specific library used in this benchmark. However, the `Date` object and its methods (`Date.parse()`) are part of the JavaScript standard library.

**Special JS feature or syntax:**

No special JavaScript features or syntax are being tested or utilized in this benchmark.

**Benchmark Preparation Code:**

The provided JSON does not include any preparation code for the benchmark. This suggests that the tests can be run directly using the `Date.parse()` function and the input date string without requiring additional setup or configurations.

**Other alternatives:**

There are alternative approaches to handling dates in JavaScript, such as:

*   Using a dedicated date library like Moment.js.
*   Utilizing modern JavaScript features like `Intl.DateTimeFormat` for formatting dates.
*   Implementing custom date parsing logic using regular expressions or other techniques.

However, these alternatives may not be relevant to this specific benchmark, which focuses on comparing the performance of two simple approaches: direct `Date.parse()` and deferred date creation.

Related benchmarks:

Comparing date allocation (version: 0)

Checking how expensive creating a date is compared to deferring it to be done in a lazy fashion later on.

Comparing performance of: Date from string vs Just assigning string

Created: one year ago by: Guest

Jump to the latest result

Date from string

Just assigning string

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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