Benchmark: split vs split vs split vs slice+indexOf

Script Preparation code:

var a = "slkfzesqdmkfbaczeiuncamzieurnamziuenramcizurnmcaizunermdzdezedzdjg qmzzpeoriucbyazpoeruycbaozecyrbazdzedksjdf zedazerbcazoyrbcoaizuyebrcoizedzmkqjsd fzedzedzedzedmkj";

Tests:

split1
a.split(" ", 1);
split10
a.split(" ", 1)[0];
split0
a.split(" ")[0];
slice
a.slice(0, a.indexOf(" "));

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
split1
split10
split0
slice

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.1:latest, generated one month ago):

LLMs can make mistakes. Check important info.

Let's dive into the benchmark definition.

**What is being tested?**

The test case is comparing the performance of four different methods to extract the first substring in a long string that contains multiple spaces.

**Options compared:**

1. `a.split(" ", 1);` - This method splits the string `a` by a single space into an array, and returns the first element of the array.
2. `a.split(" ", 1)[0];` - Similar to option 1, but with an additional indexing step `[0]` to access the first element of the array.
3. `a.split(" ")[0];` - This method splits the string `a` by any number of spaces into an array, and returns the first element of the array.
4. `a.slice(0, a.indexOf(" "));` - This method uses the `slice()` method to extract a substring from index 0 to the index of the first space (found using the `indexOf()` method).

**Pros/Cons:**

* **split() with limit**: Option 1 is efficient because it splits the string only up to the first space, reducing unnecessary processing. However, it may not work correctly if there are no spaces in the string.
* **split() without limit**: Options 2 and 3 split the entire string by any number of spaces, which can be slower due to excessive splitting and indexing operations. Option 3 is slightly faster than option 2 since it doesn't need an additional indexing step.
* **slice() with indexOf()**: Option 4 uses `indexOf()` to find the first space, and then `slice()` to extract the substring up to that point. This approach may be slower than using `split()` since it involves two separate operations.

**Other considerations:**

* The test string is very long, containing multiple spaces. This might skew the results if the tested methods have different performance characteristics for short vs. long strings.
* The test environment (Android 4.2.2 on a tablet) may not be representative of other platforms or devices.

No special libraries or JavaScript features are used in this test case.

Latest run results:

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

User agent: Mozilla/5.0 (Android 4.2.2; Tablet; rv:68.0) Gecko/68.0 Firefox/68.0

Browser/OS: Android 4 on Android 4.2.2

View result in a separate tab

Test name	Executions per second
split1	419981.3 Ops/sec
split10	468060.0 Ops/sec
split0	235142.4 Ops/sec
slice	1836541.9 Ops/sec

Related benchmarks:

split vs split vs split vs slice+indexOf (version: 0)

Comparing performance of: split1 vs split10 vs split0 vs slice

Created: 2 years ago by: Guest

Jump to the latest result

split1

split10

split0

slice

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.1:latest, generated one month ago):