Benchmark: performance float vs getTime int

Script Preparation code:

this.last_time = 0;
this.framerate = 60;

Tests:

performance.now
let time = performance.now(); this.last_time = this.last_time || time - (this.framerate * 1000); let time_diff = (time - this.last_time) / 1000;
getTime
let time = (new Date()).getTime(); this.last_time = this.last_time || time - (this.framerate * 1000); let time_diff = (time - this.last_time) / 1000;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
performance.now
getTime

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's dive into the details of the provided benchmark and explain what is being tested, compared, and the pros and cons of each approach.

**What is being tested?**

The provided benchmark tests two approaches to measure the time elapsed between consecutive executions of a JavaScript function: `performance.now()` and `getTime()`. The test aims to compare the performance differences between these two methods in measuring time.

**Options compared:**

1. **`performance.now()`**: This method measures the time elapsed since the last call to `performance.now()`, which returns the current system time in fractional seconds.
2. **`getTime()`**: This method returns the number of milliseconds since the Unix epoch (January 1, 1970) at the start of the program.

**Pros and Cons:**

*   **`performance.now()`**
    *   Pros:
        *   Provides high-resolution timing measurements in fractional seconds.
        *   More accurate for measuring short time intervals.
        *   Less prone to variations due to system load or other environmental factors.
    *   Cons:
        *   Only works within a JavaScript context (not outside of it).
        *   May not provide a consistent baseline across different systems.

*   **`getTime()`**
    *   Pros:
        *   Works both inside and outside of the JavaScript context.
        *   Provides a consistent baseline across different systems.
    *   Cons:
        *   Offers lower resolution (millisecond precision) compared to `performance.now()`.
        *   May be less accurate for measuring short time intervals due to variations in system load or other environmental factors.

**Other considerations:**

*   **Accuracy**: When evaluating the accuracy of a timing measurement, consider both the inherent precision of the method and any external factors that might affect it (e.g., system load, CPU frequency changes).

**Library usage:**

In this benchmark, no libraries are explicitly mentioned or used. However, it's worth noting that some JavaScript environments or implementations may have built-in libraries or extensions for timing measurements.

**Special JS features or syntax:**

*   The `performance.now()` method is a special feature provided by the Web APIs (Web Performance and Navigation APIs), which allows developers to measure time with high resolution in the browser.
*   There are no explicit mentions of any other special JavaScript features or syntax in this benchmark.

**Other alternatives:**

If you're looking for alternative methods to measure time, some options might include:

*   **`Date.now()`**: A less accurate equivalent to `getTime()`.
*   **`requestAnimationFrame()` + `Date.now()`**: Combining the `requestAnimationFrame()` callback with the `Date.now()` method can provide a high-resolution timing measurement.
*   **`setTimeout()`**: Using `setTimeout()` with a short delay and measuring the elapsed time might also be considered. However, it may not offer the same accuracy as `performance.now()`.

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/111.0.0.0 Safari/537.36

Browser/OS: Chrome 111 on Windows

View result in a separate tab

Test name	Executions per second
performance.now	3759734.5 Ops/sec
getTime	4579087.0 Ops/sec

Related benchmarks:

performance float vs getTime int (version: 0)

Comparing performance of: performance.now vs getTime

Created: one year ago by: Guest

Jump to the latest result

performance.now

getTime

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

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