Benchmark: test b@b regexp list

Tests:

regexp of list
new RegExp("(^([^./]+\\.)*slack\\.com/)|(^([^./]+\\.)*microsoft\\.com/)|(^([^./]+\\.)*beamy\\.io/)").test("sub1.sub2.beamy.io/");
list of regexps
new RegExp("^([^./]+\\.)*slack\\.com/").test("sub1.sub2.beamy.io/"); new RegExp("^([^./]+\\.)*microsoft\\.com/").test("sub1.sub2.beamy.io/"); new RegExp("^([^./]+\\.)*beamy\\.io/").test("sub1.sub2.beamy.io/");

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
regexp of list
list of regexps

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

I'll break down the benchmark test cases and explain what's being tested.

**What is being tested?**

The provided benchmark tests regular expression (RegExp) performance in JavaScript, specifically:

1. `regexp of list`: This test case uses a single RegExp object to match different strings against three patterns (`slack.com`, `microsoft.com`, and `beamy.io`). The test checks how many times the RegExp object can be executed in one second.
2. `list of regexps`: This test case creates multiple separate RegExp objects for each pattern (three in this case) and executes them individually in a loop. It then repeats the process of executing all three Regexp objects together.

**Options compared**

The two main options being compared are:

1. **Single RegExp object vs. Multiple separate RegExp objects**: The first test case uses a single RegExp object, while the second test case creates multiple separate RegExp objects for each pattern.
2. **Sequential execution vs. Combined execution**: In the `list of regexps` test case, the Regexp objects are executed individually in a loop (sequential), whereas in the `regexp of list` test case, all three Regexp objects are executed together.

**Pros and Cons**

**Single RegExp object:**

Pros:

* Less memory usage, as only one RegExp object is created.
* Can be faster, since it's not creating multiple instances of the same function.

Cons:

* May lead to slower performance due to repeated recompilation of the RegExp object.
* More difficult to maintain and debug, if the patterns change.

**Multiple separate RegExp objects:**

Pros:

* Faster execution, as each Regexp object is only compiled once.
* Easier maintenance and debugging, since each pattern can be modified independently.

Cons:

* More memory usage, due to multiple instances of the same function being created.
* May lead to slower performance if the number of patterns increases.

**Other considerations**

In general, creating separate RegExp objects for different patterns can be beneficial when:

* The patterns are complex or have many alternatives.
* The patterns need to be modified independently.
* Speed is a critical factor in your application.

However, creating a single RegExp object with multiple patterns can be beneficial when:

* The number of patterns is small (less than 10-15).
* Memory usage is a concern.
* Recompilation of the RegExp object is not necessary due to caching.

**Library and special JS features**

There are no libraries mentioned in the provided benchmark. However, it's worth noting that some JavaScript engines have built-in optimizations for Regexp performance, such as:

* Caching: Some engines cache compiled Regexp objects to reduce recompilation time.
* Just-In-Time (JIT) compilation: Engines like V8 (used by Chrome) can JIT compile Regexp patterns to generate machine code.

**Test user special JS feature**

There are no specific JavaScript features mentioned in the provided benchmark. However, it's worth noting that some benchmarks might test performance of specific features like:

* `String.prototype.replace()`
* `Array.prototype.indexOf()`
* `Object.keys()` and friends

In conclusion, this benchmark is testing the performance of regular expression execution in JavaScript, specifically comparing the use of a single RegExp object versus multiple separate Regexp objects. The results can provide insights into the optimal way to handle complex patterns and caching strategies for improved performance.

Latest run results:

Run details: (Test run date: 9 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/121.0.0.0 Safari/537.36

Browser/OS: Chrome 121 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
regexp of list	2884786.0 Ops/sec
list of regexps	1955119.6 Ops/sec

Related benchmarks:

test b@b regexp list (version: 0)

Comparing performance of: regexp of list vs list of regexps

Created: 9 months ago by: Guest

Jump to the latest result

regexp of list

list of regexps

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):