Benchmark: Compare substring with less than threshold with doing nothing 1

Script Preparation code:

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

Tests:

do nothing
var anotherStr = str + "...";
substring with more than needed
var substring = str.substring(0, 1000) + "...";

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
do nothing
substring with more than needed

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 27 days ago):

LLMs can make mistakes. Check important info.

Let's break down the provided JSON that represents the JavaScript microbenchmark, specifically focusing on what is being tested.

**Benchmark Definition**

The benchmark measures the performance difference between two approaches:

1. **"do nothing"`**: This approach simply appends an additional string to the original string (`str`) without modifying it.
2. **"substring with more than needed"`**: This approach creates a substring of `str` by specifying a length that exceeds the actual length of `str`. The resulting string is then appended with another string.

**What's being tested?**

The benchmark tests the performance impact of these two approaches on the original string (`str`). Specifically, it measures:

* How much time and resources are spent when appending an additional string to the original string (i.e., "do nothing")
* How much time and resources are spent when creating a substring that is longer than necessary and then appending another string (i.e., "substring with more than needed")

**Options comparison**

The two approaches differ in their:

* **Modifying vs. non-modifying**: The "do nothing" approach simply appends to the original string, while the "substring with more than needed" approach creates a new substring and then appends to it.
* **String allocation**: The "substring with more than needed" approach requires allocating additional memory for the unnecessary substring before appending.

**Pros and Cons**

* **"do nothing"`**
	+ Pros: Minimal overhead, simple append operation
	+ Cons: Potential performance impact due to string creation and appends (though likely negligible)
* **"substring with more than needed"`
	+ Pros: Efficient use of memory for the original string, no additional appends required after substring creation
	+ Cons: Creates unnecessary temporary storage for the excess substring

**Library usage**

There is no explicit library mentioned in the provided JSON. However, it's likely that JavaScript engines like V8 (used by Chrome) or SpiderMonkey (used by Firefox) would provide optimizations and internal functions to handle string manipulation efficiently.

**Special JS features**

The benchmark doesn't seem to utilize any specific JavaScript feature or syntax beyond standard string operations.

Latest run results:

Run details: (Test run date: 3 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.212 Safari/537.36

Browser/OS: Chrome 90 on Windows

View result in a separate tab

Test name	Executions per second
do nothing	5241991.5 Ops/sec
substring with more than needed	4104877.2 Ops/sec

Related benchmarks:

Compare substring with less than threshold with doing nothing 1 (version: 0)

Comparing performance of: do nothing vs substring with more than needed

Created: 3 years ago by: Guest

Jump to the latest result

do nothing

substring with more than needed

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 27 days ago):