Benchmark: Date(number) vs Date(Number(bigint))

Script Preparation code:

var timestampBigInt = 1665060929302n
var timestampNumber = 1665060929302

Tests:

new Date - bigint to number conversion
const date = new Date(Number(timestampBigInt))
new Date - from number
const date = new Date(timestampNumber)

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
new Date - bigint to number conversion
new Date - from number

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/17.1.2 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
new Date - bigint to number conversion	4123243.0 Ops/sec
new Date - from number	6607980.5 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 explain the benchmark.

**Benchmark Overview**

The provided benchmark measures the performance difference between two approaches when creating a new `Date` object in JavaScript:

1. Converting a 64-bit BigInt value to a number using `Number()`.
2. Passing a regular number (not BigInt) directly to the `Date` constructor.

**Options Compared**

There are two options compared:

1. **BigInt conversion**: This approach converts the input BigInt value to a number using `Number()` before passing it to the `Date` constructor.
	* Pros: Works with both JavaScript engines and browsers that support BigInt, potentially providing accurate results.
	* Cons: May incur additional overhead due to the conversion step, which can affect performance.
2. **Direct number pass**: This approach passes a regular number directly to the `Date` constructor without any conversions.

**Pros and Cons**

The choice between these two approaches depends on the specific use case and requirements. If you need to handle BigInt values, using `Number()` may be necessary for compatibility reasons. However, if you're working with regular numbers only, passing them directly might be faster due to reduced overhead.

In general, when working with JavaScript engines or browsers that support BigInt, using the direct number pass approach can provide better performance. Conversely, if you need to handle both numeric and BigInt values, using `Number()` for conversion is a safer choice.

**Libraries and Features**

There are no specific libraries mentioned in this benchmark. However, it's worth noting that JavaScript engines like V8 (used by Chrome) and SpiderMonkey (used by Firefox) have their own optimizations and features that might affect performance.

Regarding special JavaScript features or syntax, the benchmark doesn't mention anything related to ES6+ features, WebAssembly, or other advanced topics.

**Other Alternatives**

If you're interested in exploring alternative approaches or benchmarks, here are a few examples:

1. **Date.now() vs Date.now() with BigInt**: Compare the performance of `Date.now()` when used with and without BigInt support.
2. **Performance comparison between JavaScript engines**: Benchmark various JavaScript engines (e.g., V8, SpiderMonkey, JavaScriptCore) to see which one performs best for specific tasks.
3. **Benchmarking string manipulation libraries**: Compare the performance of popular string manipulation libraries like Lodash or Ramda.

Keep in mind that these alternatives might require more setup and configuration than this simple benchmark.

I hope this explanation helps! Let me know if you have any further questions.

Related benchmarks:

Date(number) vs Date(Number(bigint)) (version: 0)

Comparing performance of: new Date - bigint to number conversion vs new Date - from number

Created: 3 years ago by: Guest

Jump to the latest result

new Date - bigint to number conversion

new Date - from number

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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