Benchmark: split vs substr - MeasureThat.net

Script Preparation code:

var str = "2020-02-11 17:53:41";

Tests:

split
var parts = str.split(' '); parts = parts[0].split('-'); year = parts[0] month = parts[1] day = parts[2]
substr
year = str.substr(0,4); month = str.substr(5,2); day = str.substr(8,2);

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
split
substr

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

Let's dive into explaining the benchmark and its options.

**Benchmark Overview**

The provided JSON represents a JavaScript microbenchmark that compares two approaches to extract date components from a string: `split` and `substr`. The benchmark is designed to measure which approach is faster on various platforms and browsers.

**Options Compared**

There are two options compared in this benchmark:

1. **`split`**: This method splits the input string into an array of substrings using a specified delimiter (in this case, a space and then a hyphen). The date components are then extracted from the resulting array.
2. **`substr`**: This method extracts specific parts of the original string using substring operations.

**Pros and Cons**

Here's a brief analysis of each approach:

*   `split`:
    *   Pros: Simple to understand, widely supported in modern browsers, and can be easily adapted for more complex parsing tasks.
    *   Cons: May have performance implications due to the overhead of creating an array and iterating through its elements. Additionally, it may not be as efficient for very large input strings or those with multiple delimiters.
*   `substr`:
    *   Pros: Can be faster for specific use cases where extracting a small substring is required, reducing overhead compared to using `split`.
    *   Cons: Less readable and maintainable due to its reliance on magic numbers (e.g., "2020-02-11 17:53:41" -> year=substr(0,4), etc.) that may not be immediately clear for non-experts.

**Library Usage**

There is no explicit library usage in this benchmark. However, it's worth noting that both `split` and `substr` are native JavaScript functions, which means they don't rely on external libraries to function.

**Special JS Features or Syntax**

No special JavaScript features or syntax are used in these benchmarks. They focus solely on the performance differences between two basic string manipulation methods.

**Alternatives**

For measuring JavaScript performance, some alternatives include:

*   **BenchmarkDotNet**: An open-source benchmarking framework specifically designed for .NET and JavaScript applications.
*   **JSHint**: While primarily a linter, JSHint can also be used to run benchmarks. However, it's not as tailored towards performance measurements as BenchmarkDotNet or the provided MeasureThat.net framework.

In summary, this benchmark provides a clear comparison between two approaches for extracting date components from a string in JavaScript: `split` and `substr`. It showcases their performance differences on various platforms and browsers, offering insights into the trade-offs of each method.

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:72.0) Gecko/20100101 Firefox/72.0

Browser/OS: Firefox 72 on Ubuntu

View result in a separate tab

Test name	Executions per second
split	2441679.8 Ops/sec
substr	12382318.0 Ops/sec

Related benchmarks:

split vs substr (version: 0)

Comparing performance of: split vs substr

Created: 4 years ago by: Guest

Jump to the latest result

split

substr

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):