Benchmark: Performance Test: substring vs split pop

Script Preparation code:

var string = "I am the god of hellfire, and I bring you..."

Tests:

substring
var substring = string.substring(string.indexOf(',') + 1)
split with pop
var substring = string.split(',').pop();

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
substring
split with pop

Fastest: N/A

Slowest: N/A

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/131.0.0.0 Safari/537.36

Browser/OS: Chrome 131 on Windows

View result in a separate tab

Test name	Executions per second
substring	134365472.0 Ops/sec
split with pop	27212708.0 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested, compared, and analyzed.

**What is being tested?**

The benchmark is comparing two approaches to extract a substring from a given string:

1. `substring` method: This method returns a new string that includes a part of the original string, starting from the index specified by `string.indexOf(',') + 1`.
2. `split` method with `pop`: This method splits the string into an array using the comma (``,) as the separator and then returns the last element of the resulting array.

**Options compared**

The two options are being compared in terms of their performance, specifically the number of executions per second (`ExecutionsPerSecond`) on a specific browser version and device platform (Chrome 127 on Windows Desktop).

**Pros and cons of each approach:**

1. `substring` method:
	* Pros:
		+ Directly extracts the desired substring without modifying the original string.
		+ May be more efficient for small strings or precise substring extraction.
	* Cons:
		+ Can lead to a slower performance due to the `indexOf` method's overhead and possible string index bounds checking.
2. `split` method with `pop`:
	* Pros:
		+ Can be faster for large strings or multiple substrings, as it uses a more optimized algorithm under the hood.
	* Cons:
		+ Returns an array element instead of a direct substring, which may incur additional overhead.

**Library usage:**

There is no explicit library mentioned in the benchmark definition or test cases. However, the `split` method relies on the built-in `Array.prototype.split()` and `Array.prototype.pop()` methods, which are part of the JavaScript standard library.

**Special JS features or syntax:**

The `indexOf` method used in the `substring` approach is a built-in JavaScript function that can be slow for large strings. While not explicitly mentioned, its usage might affect performance.

**Benchmark preparation code:**

The provided script preparation code creates a sample string `string = "I am the god of hellfire, and I bring you..."`. This string is likely chosen to contain a comma (`,`) that can be used as a delimiter for splitting. The HTML preparation code is empty, indicating no additional setup or configuration for the benchmark.

**Alternative approaches:**

Other alternatives for extracting substrings from strings might include:

1. `slice()`: A method that creates a new string by taking a subset of characters from the original string.
2. Regular expressions (regex): Can be used to match and extract specific patterns within the string, offering more flexibility than substring or split methods.
3. Library-based solutions: Depending on the specific use case, libraries like String.prototype.substr(), String.prototype.slice() or regex libraries might provide optimized or feature-rich substring extraction functions.

Keep in mind that each approach has its trade-offs, and the chosen method will depend on factors such as performance requirements, code readability, and maintainability.

Related benchmarks:

Performance Test: substring vs split pop (version: 0)

Comparing performance of: substring vs split with pop

Created: one year ago by: Guest

Jump to the latest result

substring

split with pop

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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