Benchmark: Should you cache Intl.DateTimeFormat (simple key)?

Script Preparation code:

FORMAT = { timeZone: 'Europe/Moscow', day: '2-digit', month: 'short', year: 'numeric' }
cache = new Map()

Tests:

No caching
const date = new Intl.DateTimeFormat('en-AU', FORMAT).format(new Date())
With simple cache
const key = FORMAT.timeZone; let formatter = cache.get(key) if (!formatter) { formatter = new Intl.DateTimeFormat('en-AU', FORMAT) cache.set(key, formatter) } const date = formatter.format(new Date())

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
No caching
With simple cache

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/116.0.5845.1064 YaBrowser/23.9.1.1064 (beta) Yowser/2.5 Safari/537.36

Browser/OS: Yandex Browser 23 on Linux

View result in a separate tab

Test name	Executions per second
No caching	7513.3 Ops/sec
With simple cache	488701.8 Ops/sec

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

LLMs can make mistakes. Check important info.

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

**What is being tested?**

MeasureThat.net is testing two approaches to creating an `Intl.DateTimeFormat` object:

1. Creating a new instance of `Intl.DateTimeFormat` without caching (also known as "no caching").
2. Caching instances of `Intl.DateTimeFormat` using a simple string as the key (also known as "with simple cache").

**Options compared**

The benchmark is comparing two options:

* Option 1: Create a new instance of `Intl.DateTimeFormat` each time it's needed, without storing any instances in memory.
* Option 2: Cache instances of `Intl.DateTimeFormat` using a simple string (`FORMAT.timeZone`) as the key. This means that if an instance is created before with the same settings, it will be retrieved from the cache instead of creating a new one.

**Pros and cons**

Here are some pros and cons of each approach:

**No Caching (Option 1)**

Pros:

* Simple to implement
* No memory usage concerns
* No potential for stale data or inconsistencies

Cons:

* Creating a new instance of `Intl.DateTimeFormat` can be slow, especially if the same settings are used frequently.
* Memory usage increases linearly with the number of instances created.

**With Simple Cache (Option 2)**

Pros:

* Can improve performance by reusing existing instances
* Reduces memory usage compared to Option 1

Cons:

* Adds complexity due to caching mechanism
* If an instance is not cached, it needs to be created, which can still be slow.
* There's a risk of stale data or inconsistencies if the cache is not updated properly.

**Other considerations**

In this benchmark, MeasureThat.net is using a simple string (`FORMAT.timeZone`) as the key for caching. This approach has some limitations:

* If multiple instances with different settings are cached, it may lead to unexpected behavior.
* The cache will only work if the same settings are used exactly, including all options (e.g., `day`, `month`, `year`).

**Library and its purpose**

The `Intl.DateTimeFormat` object is a part of the Internationalization API in JavaScript. Its purpose is to format dates and times according to the user's locale preferences.

In this benchmark, the `FORMAT` object defines the settings for the date and time formatting, such as language (`'en-AU'`), timezone (`'Europe/Moscow'`), day format (`'2-digit'`), month format (`'short'`), and year format (`'numeric'`).

Related benchmarks:

Should you cache Intl.DateTimeFormat (simple key)? (version: 1)

Testing creating a new Intl.DateTimeFormat each time vs. caching it using simple string as the key.

Comparing performance of: No caching vs With simple cache

Created: 2 years ago by: Registered User

Jump to the latest result

No caching

With simple cache

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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